North Korea’s Nuclear Weapons: Technical Issues
Congressional research reportApr 3, 2013
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North Korea’s Nuclear Weapons:
Technical Issues
Mary Beth Nikitin
Specialist in Nonproliferation
April 3, 2013
Congressional Research Service
7-....
www.crs.gov
RL34256
CRS Report for Congress
Prepared for Members and Committees of Congress
North Korea’s Nuclear Weapons: Technical Issues
Summary
This report summarizes what is known from open sources about the North Korean nuclear
weapons program—including weapons-usable fissile material and warhead estimates—and
assesses current developments in achieving denuclearization. Little detailed open-source
information is available about the DPRK’s nuclear weapons production capabilities, warhead
sophistication, the scope and success of its uranium enrichment program, or extent of its
proliferation activities. In total, it is estimated that North Korea has between 30 and 50 kilograms
of separated plutonium, enough for at least half a dozen nuclear weapons. North Korea’s
plutonium production reactor at Yongbyon has been shuttered since its cooling tower was
destroyed under international agreement in June 2008. However, on April 1, 2013, North Korea
said it would resume operation of its plutonium production reactor. Experts estimate it will take
approximately six months to restart. This would provide North Korea with approximately one
bomb’s worth of plutonium per year.
While North Korea’s weapons program has been plutonium-based from the start, in the past
decade, intelligence emerged pointing to a second route to a bomb using highly enriched uranium.
North Korea openly acknowledged a uranium enrichment program in 2009, but has said its
purpose is the production of fuel for nuclear power. In November 2010, North Korea showed
visiting American experts early construction of a 100 MWT light-water reactor and a newly built
gas centrifuge uranium enrichment plant, both at the Yongbyon site. The North Koreans claimed
the enrichment plant was operational, but this has not been independently confirmed. U.S.
officials have said that it is likely other, clandestine enrichment facilities exist. Enrichment (as
well as reprocessing) technology can be used to produce material for nuclear weapons or fuel for
power reactors. An enrichment capability could potentially provide North Korea with a faster way
of making nuclear material for weapons and therefore is of great concern to policymakers.
North Korea has made multiple policy statements in the past year asserting its nuclear weapons
status: in May 2012, North Korea changed its constitution to say that it was a “nuclear-armed
state.” In January 2013, North Korea said that no dialogue on denuclearization “would be
possible” and it would only disarm when all the other nuclear weapon states also disarm. In
March 2013, North Korea stated its goal of expanding its nuclear weapons program.
Many experts believe that the prime objective of North Korea’s nuclear program is to develop a
nuclear warhead that could be mounted on North Korea’s intermediate-range and long-range
missiles. This was confirmed by North Korean official statements in late March 2013.
Miniaturization of a nuclear warhead would likely require additional nuclear and missile tests. In
January 2013, a North Korean statement said that it would respond with a nuclear test “of higher
level.” On February 12, 2013, the North Korean official news agency announced a “successful”
underground nuclear detonation, and seismic monitoring systems measured a resulting earthquake
that was 5.1 in magnitude. This is magnitude is slightly higher than past tests, but yield estimates
are still uncertain. The South Korean Ministry of Defense estimated that the test yield was
between 6 and 7 kilotons, while the U.S. Director of National Intelligence so far has said
“approximately several kilotons.” North Korea claimed that the February 12, 2013, nuclear test
was to develop a “smaller and light” warhead. At a minimum, the test would likely contribute to
North Korea’s ability to develop a warhead that could be mounted on a long-range missile. To
date, no open source data on test emissions is available that might show whether the North
Koreans tested a uranium or plutonium device. This information could help determine the type
and sophistication of the North Korean nuclear warhead design, about which little is known.
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North Korea’s Nuclear Weapons: Technical Issues
Contents
Background ...................................................................................................................................... 1
Weapons Production Milestones ...................................................................................................... 3
Estimating Nuclear Warheads and Plutonium Stocks ................................................................ 4
Plutonium Production and Reactors .......................................................................................... 5
Uranium Enrichment........................................................................................................................ 7
North Korean Statements on Its Enrichment Program .............................................................. 9
U.S. Intelligence Assessments ................................................................................................. 10
Uranium Enrichment and Nuclear Negotiations...................................................................... 12
Nuclear Testing .............................................................................................................................. 13
The February 12, 2013, Nuclear Test ...................................................................................... 14
The May 25, 2009, Nuclear Test ............................................................................................. 14
The October 9, 2006, Nuclear Test .......................................................................................... 15
Delivery Systems ........................................................................................................................... 16
Doctrine and Intent ........................................................................................................................ 17
Steps Toward Denuclearization Under the Six-Party Talks (2005-2009) ...................................... 18
Disablement ............................................................................................................................. 18
Reversing Disablement ............................................................................................................ 20
Declaration .............................................................................................................................. 21
Verification .............................................................................................................................. 23
Future Considerations .............................................................................................................. 26
The Leap Day Agreement .............................................................................................................. 27
Proliferation Issues ........................................................................................................................ 28
Issues for Congress ........................................................................................................................ 29
Funding .................................................................................................................................... 29
Authority.................................................................................................................................. 30
Policy Guidance....................................................................................................................... 31
Tables
Table 1. North Korean Nuclear Power Reactor Projects ................................................................. 7
Table 2. Disablement Steps at Yongbyon, DPRK .......................................................................... 19
Contacts
Author Contact Information........................................................................................................... 32
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North Korea’s Nuclear Weapons: Technical Issues
Background
In the early 1980s, U.S. satellites tracked a growing indigenous nuclear program in North Korea.
The North Korean nuclear program began in the late 1950s with cooperation agreements with the
Soviet Union on a nuclear research program near Yongbyon. Its first research reactor began
operation in 1967. North Korea used indigenous expertise and foreign procurements to build a
small nuclear reactor at Yongbyon (5 MWe). It was capable of producing about 6 kilograms (Kg)
of plutonium per year and began operating in 1986.1 Later that year, U.S. satellites detected high
explosives testing and a new plant to separate plutonium from the reactor’s spent fuel. In
addition, construction of two larger reactors (50 MWe at Yongbyon and 200 MWe at Taechon)
added evidence of a serious clandestine effort. Although North Korea had joined the Nuclear
Nonproliferation Treaty (NPT) in 1985 under Soviet pressure, safeguards inspections began only
in 1992, raising questions about how much plutonium North Korea had produced covertly. In
1994, North Korea pledged, under the Agreed Framework with the United States, to freeze its
plutonium programs and eventually dismantle them in return for several kinds of assistance.2 At
that time, Western intelligence agencies estimated that North Korea had separated enough
plutonium for one or two bombs. North Korea complied with the Agreed Framework, allowing
International Atomic Energy Agency (IAEA) seals—including the “canning” of spent fuel rods at
the Yongbyon reactor—and permanent remote monitoring and inspectors at its nuclear facilities.
When in 2002, U.S. negotiators reportedly presented North Korean officials with evidence of a
clandestine uranium enrichment program, the North Korean officials reportedly at first confirmed
this, then denied it publicly. The conflict quickly led to the breakdown of the Agreed Framework.
The Bush Administration argued that North Korea was in “material breach” of its obligations and,
after agreement with South Korea, Japan, and the EU (the other members of the Korean
Economic Development Organization, or KEDO), stopped the next shipment of heavy fuel oil.3
In response, North Korea kicked out international monitors, broke the seals at the Yongbyon
nuclear complex, and restarted its reactor and reprocessing plant after an eight-year freeze.
Members of the Six-Party Talks—the United States, South Korea, Japan, China, Russia, and
North Korea—began meeting in August 2003 to try and resolve the crisis. In September 2005, the
Six Parties issued a Joint Statement on how to achieve verifiable denuclearization of the Korean
Peninsula, which formed the basis for future agreements.4 Negotiations broke down, and North
Korea tested a nuclear device in October 2006.
On February 13, 2007, North Korea reached an agreement with other members of the Six-Party
Talks to begin the initial phase (60 days) of implementing the Joint Statement from September
2005 on denuclearization. Phase 1 of this agreement included the shut-down of plutonium
production at the Yongbyon nuclear complex in exchange for an initial heavy fuel oil shipment to
1
5 MWe is a power rating for the reactor, indicating that it produces 5 million watts of electricity per day (very small).
Reactors are also described in terms of million watts of heat (MW thermal).
2
See CRS Report RL33590, North Korea’s Nuclear Weapons Development and Diplomacy, by (name redacted) and
CRS Report R40095, Foreign Assistance to North Korea, by (name redacted) and Mary Beth Nikitin.
3
“Adherence To and Compliance With Arms Control, Nonproliferation and Disarmament Agreements and
Commitments,” U.S. Department of State, August 2005.
4
“Joint Statement of the Fourth Round of the Six-Party Talks, Beijing,” September 19, 2005, at http://www.state.gov/r/
pa/prs/ps/2005/53490.htm.
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North Korea. Phase 2 steps include the disablement of facilities at Yongbyon and a “complete and
correct” declaration of DPRK nuclear activities, in exchange for delivery of heavy fuel oil and
equivalent, and removal of the Trading with the Enemy Act (TWEA) and State Sponsors of
Terrorism (SST) designations. The United States provided funding and technical assistance for
disablement activities in North Korea until April 2009. Energy assistance was divided evenly
between the Six Parties in Phase 2 of the agreement. North Korea submitted a declaration of its
past plutonium production activities in June 2008 as agreed in an October 3, 2007, joint statement
on “Second-Phase Actions.”5 Thereafter, President Bush removed North Korea from the TWEA
list and notified Congress of his intent to lift the SST designation after North Korea agreed to
verification provisions. North Korea did not accept initial U.S. verification proposals, and in
September 2008, threatened to restart reprocessing plutonium. U.S. officials announced a bilateral
agreement on verification in October 2008, and the Bush Administration removed North Korea
from the SST List. The agreement was verbal, and North Korea then said that it had not agreed to
sampling at nuclear sites, a key element in verifying past plutonium production. The Six Parties
met in December 2008, but did not reach agreement on verification measures. Disablement
activities at Yongbyon continued through April 2009, when North Korea expelled international
monitors. North Korea then announced it would restart its reprocessing plant and boasted
progress in uranium enrichment technology development and soon after tested as nuclear device
(see detailed discussions below).
The February 2007 Denuclearization Action Plan did not address uranium enrichment-related
activities or the dismantlement of warheads and instead focused on shutting down and disabling
the key plutonium production facilities at Yongbyon. A third phase, to have begun after
disablement was complete and a declaration accepted by the Six Parties, was expected to deal
with all aspects of North Korea’s nuclear program, including weapons, using North Korea’s
declaration as a basis for future action. Understanding the scope of the program and the weapons
capability would require transparency and careful verification for the pledged “complete,
verifiable, irreversible” disarmament to be achieved.
Six Party Talks have not been held since spring 2009, but the United States and other countries
have held bilateral talks with the North since then. North Korea openly acknowledged a uranium
enrichment program in 2009, but has said its purpose is the production of fuel for nuclear power.
In November 2010, North Korea showed visiting American experts early construction of a 100
MWT light-water reactor and a newly built gas centrifuge uranium enrichment plant, both at the
Yongbyon site. The North Koreans claimed the enrichment plant was operational, but this has not
been independently confirmed. U.S. officials have said that it is likely other, clandestine
enrichment facilities exist. A February 2012 announcement committed North Korea to moratoria
on nuclear and long-range missile testing as well as uranium enrichment suspension at Yongbyon
under IAEA monitoring. However, an April 2012 satellite launch, which violated UN Security
Council resolutions as well as the February missile moratorium, caused a collapse of the February
agreement. Following a December 2012 satellite launch and subsequent UN Security Council
condemnation, North Korea rejected future denuclearization talks, saying it would only
denuclearize when all other nuclear weapons states also did so. A third nuclear test conducted on
February 12, 2013, could further complicate diplomatic efforts toward denuclearization.
5
Second-Phase Actions for the Implementation of the September 2005 Joint Statement, October 3, 2007,
http://www.state.gov/r/pa/prs/ps/2007/oct/93223.htm.
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Weapons Production Milestones
North Korea is widely believed to have mastered the engineering requirements of plutonium
production a decade ago and may now be focusing its efforts on mastering uranium enrichment.
Acquiring fissile material—plutonium-239 or highly enriched uranium (HEU)—is the key hurdle
in nuclear weapons development.6 Producing these two materials is technically challenging; in
comparison, many experts believe weaponization to be relatively easy.7 North Korea has
industrial-scale uranium mining and plants for milling, refining, and converting uranium; it also
has a fuel fabrication plant, a nuclear reactor, and a reprocessing plant—in short, everything
needed to produce Pu-239. It has recently been built a uranium enrichment facility at Yongbyon
that could produce HEU for weapons, or LEU reactor fuel which could be irradiated for
plutonium production. In its earlier 5 MWe nuclear reactor, North Korea used magnox fuel—
natural uranium (>99%U-238) metal, wrapped in magnesium-alloy cladding to produce
plutonium for weapons. About 8,000 fuel rods constitute a fuel core for the reactor.
When irradiated in a reactor, natural uranium fuel absorbs a neutron and then decays into
plutonium (Pu-239). Fuel that remains in the reactor for a long time becomes contaminated by the
isotope Pu-240, which can “poison” the functioning of a nuclear weapon.8 Spent or irradiated
fuel, which poses radiological hazards, must cool after removal from the reactor. The cooling
phase, estimated by some at five months, is proportional to the fuel burn-up. Reprocessing to
separate plutonium from waste products and uranium is the next step. North Korea used a
PUREX separation process, like the United States. After shearing off the fuel cladding, the fuel is
dissolved in nitric acid. Components (plutonium, uranium, waste) of the fuel are separated into
different streams using organic solvents. In small quantities, separation can be done in hot cells,
but larger quantities require significant shielding to prevent deadly exposure to radiation.9
It operated its 5 MWe nuclear reactor, is believed to have separated Pu from the spent fuel, and
has reportedly taken steps toward weaponization. In January 2004, North Korean officials showed
an unofficial U.S. delegation alloyed “scrap” from a plutonium (Pu) casting operation.10 Dr.
Siegfried Hecker, a delegation member, assessed that the stated density of the material was
consistent with plutonium alloyed with gallium or aluminum. If so, this could indicate a degree of
sophistication in North Korea’s handling of Pu metal, necessary for weapons production. But
without testing the material, Hecker could not confirm that the metal was plutonium or that it was
alloyed, or when it was produced.
6
Highly enriched uranium (HEU) has 20% or more U-235 isotope; 90% U-235 is weapons-grade.
The physical principles of weaponization are well-known, but producing a weapon with high reliability, effectiveness,
and efficiency without repeated testing presents significant challenges. Delivery systems add another layer of
challenge.
8
Plutonium that stays in a reactor for a long time (reactor-grade, with high “burn-up”) contains about 20% Pu-240;
weapons-grade plutonium contains less than 7% Pu-240.
9
Hot cells are heavily shielded rooms with remote handling equipment for working with irradiated materials. For
background, see Jared S. Dreicer, “How Much Plutonium Could Have Been Produced in the DPRK IRT
Reactor?”Science and Global Security, 2000, vol. 8, pp. 273-286, at http://www.princeton.edu/sgs/publications/sgs/pdf/
8_3Dreicer.pdf.
10
Alloying plutonium with other materials is “common in plutonium metallurgy to retain the delta-phase of plutonium,
which makes it easier to cast and shape” (two steps in weapons production). Hecker, January 21, 2004, testimony
before SFRC.
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Estimating Nuclear Warheads and Plutonium Stocks
Secretary of State Colin Powell in December 2002 stated, “We now believe [the North Koreans]
have a couple of nuclear weapons and have had them for years.”11 In February 2005, North Korea
officially announced that it had “manufactured nukes for self-defense.”12 Vice Foreign Minister
Kim Gye Gwan has previously said that North Korea possesses multiple bombs and was building
more.13
A key factor in assessing how many weapons North Korea can produce is whether North Korea
needs to use more or less material than the IAEA standards of 8 kg of Pu and 25 kg for HEU per
weapon.14 The amount of fissile material used in each weapon is determined by the design
sophistication. There is no reliable public information on North Korean nuclear weapons design.
In all, estimates of North Korea’s separated plutonium range between 30 kg and 50 kg, with an
approximate 5 kg to 6 kg of this figure having been used for the October 2006 test and an
additional amount probably used in the May 2009 test.15 This amounts to enough plutonium for
approximately five to eight nuclear weapons, assuming 6 kg per weapon. Taking the nuclear tests
into account, North Korean could possess plutonium for four to seven nuclear weapons. A 2007
unclassified intelligence report to Congress says that “prior to the test North Korea could have
produced up to 50 kg of plutonium, enough for at least a half dozen nuclear weapons” and points
out that additional plutonium is in the fuel of the Yongbyon reactor.16 North Korea claimed to
have reprocessed that fuel in the summer of 2009 (see below).
Questions arise in determining how much plutonium North Korea produced between 2003, when
the IAEA monitors were kicked out of the country and the seals were broken at Yongbyon, and
2007, when international monitoring resumed. A South Korean Defense Ministry white paper
from December 2006 estimated that North Korea had made 30 kg of weapons-grade plutonium in
the previous three years, potentially enough for five nuclear bombs. The white paper also
concurred with U.S. estimates that North Korea’s total stockpile of weapons-grade plutonium was
50 kg.17
The accounting issue was further complicated when North Korea reportedly declared a lower
number of 37 kg of separated plutonium in its declaration under the Six-Party Talks.18 No
11
Transcript of December 29, 2002, Meet the Press.
James Brooke, “North Korea says it has atom arms It will boycott talks on ending program; arsenal called selfdefense against Bush,” The New York Times, February 11, 2005.
13
“We have enough nuclear bombs to defend against a U.S. attack. As for specifically how many we have, that is a
secret.” “North Korea Admits Building More Nuclear Bombs,” ABC News, June 8, 2005, at http://abcnews.go.com/
WNT/story?id=831078&page=1.
14
IAEA Safeguards Glossary: http://www-pub.iaea.org/MTCD/publications/PDF/nvs-3-cd/PDF/NVS3_scr.pdf.
15
Siegfried Hecker estimates 40-50 kg of separated plutonium and 6 kg for the 2006 test; David Albright and Paul
Brannan’s study says 33-55 kg of separated plutonium and roughly 5 kg for the 2006 test. U.S. Assistant Secretary of
State Christopher Hill cites 50 kg in his comments. Hecker, ibid. David Albright and Paul Brannan, “The North Korean
Plutonium Stock February 2007,” Institute for Science and International Security, February 20, 2007. Christopher Hill,
“Interview on PBS NewsHour,” October 3, 2007, at http://www.state.gov/p/eap/rls/rm/2007/93274.htm.
16
Unclassified Report to Congress on Nuclear and Missile Programs of North Korea, Office of the Director of National
Intelligence, August 8, 2007.
17
“North Korea ‘serious threat’ to South,” BBC News, http://news.bbc.co.uk/2/hi/asia-pacific/6216385.stm.
18
Warren Strobel, “North Korean nuclear documents challenge CIA assertions,” McClatchy Newspapers, May 28,
(continued...)
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agreement has been reached on verifying the amount of plutonium stocks through inspections
(see discussions on declaration, verification below). In January 2009, an American scholar who
had visited Pyongyang said the North Koreans told him that 30.8 kg amount had been
“weaponized,” possibly meaning that the separated plutonium might now be in warheads. The
DPRK officials also told him that they would not allow for warheads to be inspected.19
An August 2012 report published by the Institute for Science and International Security (ISIS)
lays out three possible scenarios for fissile material production for the North Korean nuclear
weapons program based on available open-source information.20
Plutonium Production and Reactors
Estimates of plutonium production depend on a variety of technical factors, including the average
power level of the reactor, days of operation, how much of the fuel is reprocessed and how
quickly, and how much plutonium is lost in production processes. North Korean officials claimed
to have separated plutonium in hot cells as early as 1975 and tested the reprocessing plant in
1990. North Korea’s 5 MWe nuclear reactor at Yongbyon operated from 1986 to 1994. It is
estimated that North Korea produced and separated no more than 10 kg of plutonium prior to
1994.21 Its plutonium production program was then frozen between 1994 and 2003 under the
Agreed Framework. When this agreement was abandoned, North Korea restarted plutonium
production at Yongbyon.
On February 6, 2003, North Korean officials announced that the 5 MWe reactor was operating,
and commercial satellite photography confirmed activity in March. In January 2004, North
Korean officials told an unofficial U.S. delegation that the reactor was operating smoothly at
100% of its rated power. The U.S. visitors noted that the display in the reactor control room and
steam plumes from the cooling towers confirmed operation, but that there was no way of knowing
how it had operated over the last year.22
The same delegation reported that the reprocessing “facility appeared in good repair,” in contrast
to a 1992 IAEA assessment of the reprocessing plant as “extremely primitive.” According to
North Korean officials in January 2004, the reprocessing plant’s annual throughput is 110 tons of
spent fuel, about twice the fuel load of the 5 MWe reactor. Officials claimed to have reprocessed
all 8,000 fuel rods from the 5 MWe reactor between January and June 2003.23 Reprocessing the
8,000 fuel rods at that time would have yielded between 25 kg and 30 kg of plutonium, perhaps
for four to six weapons, but the exact amount of plutonium that might have been reprocessed is
unknown. In 2004, North Korean officials stated that the reprocessing campaign was conducted
continuously (in four six-hour shifts).
(...continued)
2008.
19
“N.K. says plutonium ‘weaponized’ and off-limits,” The Korea Herald, January 19, 2009.
20
David Albright and Christina Walrond, “North Korea’s Estimated Stocks of Plutonium and Weapon-Grade
Uranium,” Institute for Science and International Security (ISIS), August 16, 2012.
21
David Albright and Paul Brannan, “The North Korean Plutonium Stock February 2007.”
22
Siegfried Hecker, January 21, 2004, testimony before Senate Foreign Relations Committee.
23
“North Korea Says It Has Made Fuel For Atom Bombs,” New York Times, July 15, 2003.
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In April 2005, the 5 MWe reactor was shut down, this time to harvest fuel rods for weapons.24
The reactor resumed operations in June 2005.25 One estimate is that the reactor held between 10
kg and 15 kg of Pu in April 2005, and that North Korea could have reprocessed all the fuel rods
by mid-2006. From August 2005 to 2006, the reactor could have produced another 6 kg of Pu. In
total, North Korea could have reprocessed enough separated plutonium for another three weapons
(in addition to the estimated 4-6 bomb-worth from reprocessing the 8,000 fuel rods).26 The 5
MWe reactor was again shut down in July 2007, when the IAEA installed containment and
surveillance measures and radiation monitoring devices.27 Its cooling tower was destroyed in June
2008, and it has not been restarted. The IAEA was asked to remove its monitoring equipment and
leave the site in April 2009. In early November 2009, the North Korean news agency announced
that all 8,000 spent fuel rods in its possession had been reprocessed by the end of August.
Reprocessing at that time is estimated to have produced 7-8 kg of separated plutonium or
approximately enough for one nuclear warhead.28 However, even while the reprocessing facility
was shut down, North Korea could have built additional warheads with existing separated
plutonium because North Korea’s plutonium stocks were not under IAEA safeguards.
No construction has occurred at the 50 MWe reactor at Yongbyon or at the 200 MWe Taechon
reactor since 2002.29 They were years from completion when construction was halted.30 The 50
MWe reactor site at Yongbyon is currently being dismantled.31 The CIA estimated that the two
reactors could generate about 275 kg of plutonium per year if they were operating.32 Dr. Hecker
estimated that if the 50 MWe reactor was functioning, it would mean a tenfold increase in North
Korea’s plutonium production.33 North Korea agreed to halt work on reactors as part of the SixParty Talks. From July 2007 to April 2009, when inspectors were asked to leave, the IAEA was
monitoring to ensure that no further construction took place at these sites. Significant future
growth in North Korea’s plutonium-based arsenal would be possible only if the two larger
reactors were completed and operating, and would also depend on progress in the reported
uranium enrichment program.
In December 2010, Governor Bill Richardson went to North Korea on an unofficial visit. Press
reports and the governor’s website at that time said that North Korea was willing to negotiate the
sale of the 12,000 fresh fuel rods in storage at Yongbyon to a third party, such as South Korea.
24
“North Koreans Claim to Extract Fuel for Nuclear Weapons,” New York Times, May 12, 2005.
David Albright and Paul Brannan, “The North Korean Plutonium Stock February 2007,” Institute for Science and
International Security, February 20, 2007.
26
Technical difficulties associated with the fuel fabrication facility may have slowed how often the fuel was unloaded
from the reactor, limiting production to at most one bomb per year. Siegfried Hecker, “Report on North Korean
Nuclear Program,” Center for International Security and Cooperation, Stanford University, November 15, 2006.
27
IAEA Team Confirms Shut Down of DPRK Nuclear Facilities, http://www.iaea.org/NewsCenter/PressReleases/
2007/prn200712.html.
28
Siegfried Hecker, “The Risks of North Korea’s Nuclear Restart,” Bulletin of the Atomic Scientists, May 12, 2009,
http://www.thebulletin.org/web-edition/features/the-risks-of-north-koreas-nuclear-restart
29
Report by the Director General to the IAEA Board of Governors, “Applications of Safeguards in the Democratic
People’s Republic of Korea (DPRK),” GOV/2007/45-GC(51)/19, August 17, 2007.
30
Siegfried Hecker, “Report on North Korean Nuclear Program,” Center for International Security and Cooperation,
Stanford University, November 15, 2006.
31
Hecker January 21, 2004, testimony before SRFC.
32
CIA unclassified point paper distributed to congressional staff on November 19, 2002.
33
Siegfried Hecker, “A Return Trip to North Korea’s Yongbyon Nuclear Complex,” Center for International Security
and Cooperation, Stanford University, November 20, 2010. http://iis-db.stanford.edu/pubs/23035/HeckerYongbyon.pdf
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These fuel rods were manufactured for the 50 MWe reactor that was never built, but could be reclad to be used in the 5 MWe reactor if North Korea chose to restart it. North Korea announced
on in April 2013 that it plans to restart the 5 MWe reactor, which experts estimate would take
approximately six months.
Table 1. North Korean Nuclear Power Reactor Projects
Location
Type/Power Capacity
Status
Purpose
Yongbyon
Graphite-moderated Heavy
Water Experimental
Reactor/5 MWe
Currently shut-down;
cooling tower destroyed in
June 2009 as part of SixParty Talks; estimated
restart time would be 6
months; plans to restart
announced April 2013
Weapons-grade plutonium
production
Yongbyon
Graphite-moderated Heavy
Water Power Reactor /50
MWe
Never built; Basic
construction begun; project
halted since 1994
Stated purpose was
electricity production;
could have been used for
weapons-grade plutonium
production
Yongbyon
Experimental Light-Water
Reactor/100 MWT (25-30
MWe)
U.S. observers saw basic
construction begun in
November 2010; Reactor
dome emplaced on top of
containment structure
summer 2012
Stated purpose is electricity
production; could be used
for weapons-grade
plutonium production
Taechon
Graphite-moderated Heavy
Water Power Reactor/200
MWe
Never built; Basic
construction begun; project
halted since 1994
Stated purpose was
electricity production;
could have been used for
weapons-grade plutonium
production
Kumho District, Sinp’o
4 Light-water reactors/440
MW
Never built; part of 1985
deal with Soviet Union
when North Korea signed
the NPT; canceled by
Russian Federation in 1992
Stated purpose is electricity
production; could have
been used for weaponsgrade plutonium
production
Kumho District, Sinp’o
[KEDO Project]
2 Light-water reactors
(turn-key)/1000 MWe
Never built; part of 1994
Agreed Framework,
reactor agreement
concluded in 1999; Project
terminated in 2006 after
North Korea pulled out of
Agreed Framework
Electricity production
Uranium Enrichment
In November 2010, North Korean officials showed a visiting unofficial U.S. delegation—led by
former Los Alamos National Laboratory Director Dr. Siegfried Hecker—what they claimed was
an operating gas centrifuge uranium enrichment plant at the Yongbyon nuclear complex. In his
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trip report, Dr. Hecker estimated that the plant had 2,000 centrifuges (most likely P-2
centrifuges)34 in six cascades, with a capacity of 8,000 kg SWU/year.35
North Korea at that time claimed the uranium enrichment facility was built to produce enriched
uranium for power reactor fuel. In more recent statements, it has confirmed what the international
community suspected, that it could also be used for weapons material production. The North does
not have any functioning nuclear power reactors, but said it is in the process of building a 100
megawatt-thermal (25-30 megawatt-electric) experimental light-water reactor.36 Satellite images,
as well as visitors to the site, confirm initial construction.37 The reported size of the enrichment
plant would match the annual fuel needs for the proposed 100 MWT reactor, which would require
3.5% low-enriched uranium fuel. However, the plant could be altered to produce 40 kg of 90%
highly enriched uranium per year.38 Highly enriched uranium can be used for weapons, while
low-enriched uranium cannot.39
While it was known prior to Dr. Hecker’s visit that North Korea was pursuing a uranium
enrichment capacity, many analysts were surprised at the size and sophistication of the plant.40
Although North Korea’s weapons program has been plutonium-based from the start, in the past
decade, intelligence had emerged pointing to it pursuing a second route to a nuclear bomb using
highly enriched uranium. Even before North Korea unveiled the facility in November 2010, there
was some certainty that North Korea had parts and plans for such a program, but far less certainty
over how far this program had developed.
In particular, this revelation raises questions about North Korea’s domestic capability to
manufacture components, as well as how and when Pyonyang obtained any equipment or
materials for the facility. Analysts point to a history of cooperation with Pakistan, particularly
34
Hecker’s assumption is based on the chief process engineer’s comment that the rotors were made of “iron”. P-2
centrifuges use rotors made of maraging steel (vs. high-strength aluminum for the P-1 centrifuges). See Siegfried
Hecker, “A Return Trip to North Korea’s Yongbyon Nuclear Complex,” Center for International Security and
Cooperation, Stanford University, November 20, 2010. http://iis-db.stanford.edu/pubs/23035/HeckerYongbyon.pdf
35
Ibid. A SWU is a “separative work unit”, and refers to the thermodynamic work needed to produce nuclear fuel. For
a description of SWU and comparison chart for SWU capacities at enrichment facilities worldwide, see page 13 of CRS
Report RL34234, Managing the Nuclear Fuel Cycle: Policy Implications of Expanding Global Access to Nuclear
Power, coordinated by Mary Beth Nikitin.
36
Preliminary construction was shown to an earlier unofficial U.S. delegation from the Korea Economic Institute, led
by Amb. Charles “Jack” Pritchard.
37
ISIS Imagery Brief, “New Satellite Imagery of Yongbyon Shows Construction Progress on Experimental Reactor,”
Institute for Science and International Security website, November 18, 2010. http://isis-online.org/uploads/isis-reports/
documents/Yongbyon_Light_Water_Reactor_Construction_18November2010_200PM.pdf
38
Siegfried Hecker, Comments at the Korean Economic Institute, November 23, 2010. The International Atomic
Energy Agency estimates the amount of HEU needed to make a nuclear explosive device (“significant quantity”) is
25kg of uranium enriched at 20% or more. http://www-pub.iaea.org/MTCD/publications/PDF/nvs-3-cd/PDF/
NVS3_prn.pdf
39
North Korean representatives reportedly told New Mexican Governor Bill Richardson during an unofficial visit to
Pyongyang in December 2010 that they would be willing to invite International Atomic Energy Agency (IAEA)
inspectors back into the country to monitor the enrichment plant at Yongbyon, and presumably verify that it was not
producing highly enriched uranium. Chris Buckley, “North Korea to allow in IAEA inspectors—Richardson,” Reuters,
December 21, 2010.
40
David Albright and Paul Brannan, Taking Stock: North Korea’s Uranium Enrichment Program, The Institute for
Science and International Security, October 8, 2010. http://www.isis-online.org/uploads/isis-reports/documents/
ISIS_DPRK_UEP.pdf
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through the A. Q. Khan network, and multiple reports of transshipments through China.41 The
scale of the plant at Yongbyon could suggest North Korea possesses research level facilities
elsewhere in the country. Another concern is that a clandestine facility might exist that is
configured to produce HEU for the North Korean nuclear weapons program. U.S. Ambassador to
the IAEA Glyn Davies told the IAEA Board of Governors in December 2010 that the United
States believes it is likely that other, clandestine uranium enrichment facilities exist in locations
other than Yongbyon.42 A pilot-scale centrifuge plant would likely be needed to serve as a test-bed
for the larger plants, perhaps consisting of a few hundred centrifuges.
Pakistani President Musharraf revealed in his September 2006 memoir, In the Line of Fire, that
Abdul Qadeer Khan—chief scientist in Pakistan’s nuclear weapons program who proliferated
nuclear weapons technology for profit—”transferred nearly two dozen P-1 and P-2 centrifuges to
North Korea. He also provided North Korea with a flow meter, some special oils for centrifuges,
and coaching on centrifuge technology, including visits to top-secret centrifuge plants.”43
According to press reports, North Korea said it had imported 150 tons of high-strength aluminum
tubes from Russia that could be used in a uranium enrichment program in the 2002-2003 period.44
It is not known where North Korea develops or manufactures centrifuges itself. As described in
the United Nations Panel of Experts on North Korea report of June 2012, there is some debate
whether North Korea has the capacity to manufacture the specialized equipment required for
centrifuges, such as maraging steel or high-strength aluminum, or whether it could have imported
the components. Some experts posit that North Korea could have built a centrifuge based on a
less sophisticated design with less stringent quality requirements. Based on what has been
reported on procurements of relevant equipment, Former IAEA Safeguards Director Olli
Heinonen in an April 2012 article estimated that North Korea was likely developing a 5,000
centrifuge enrichment capacity, plus spares.45
North Korean Statements on Its Enrichment Program
Until May 2009, North Korea denied the existence of a highly enriched uranium program for
weapons. North Korea had threatened in April 2009 that it would build a light-water reactor if the
U.N. Security Council did not apologize for its condemnation of the North’s missile test.
Following the June 12 U.N. Security Council Resolution condemning North Korea’s nuclear test,
Pyongyang issued a statement: “The process of uranium enrichment will be commenced.” The
statement also said that “pursuant to the decision to build its own light-water reactor, enough
success has been made in developing uranium enrichment technology to provide nuclear fuel to
41
David Albright and Paul Brannan, Taking Stock: North Korea’s Uranium Enrichment Program, The Institute for
Science and International Security, October 8, 2010. http://www.isis-online.org/uploads/isis-reports/documents/
ISIS_DPRK_UEP.pdf
42
Amb. Glyn Davies, “U.S. Statement to the IAEA: DPRK,” IAEA Board of Governors Meeting, December 2-3, 2010,
http://vienna.usmission.gov/101202dprk.html
43
Pervez Musharraf, In the Line of Fire: A Memoir, (New York: Free Press, September 2006), p. 296.
44
“NK Admits to Buying Aluminum Tubes,” KBS World News, September 27, 2007, and Takashi Sakamoto, “DPRK
Admits To Importing Aluminum Tubes From Russia for Uranium Enrichment,” Yomiuri Shimbun, in Japanese,
Translated by BBC Monitoring Asia Pacific, October 26, 2007.
45
Olli Heinonen, “The North Korean Nuclear Program in Transition,” 38North.org, April 26, 2012, http://38north.org/
2012/04/oheinonen042612/.
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allow the experimental procedure.”46 In the June statement, North Korea was apparently saying it
would, at a minimum, start the experimental enrichment of uranium for fuel.47 Pyongyang offered
a further statement in September 2009: “experimental uranium enrichment has successfully been
conducted to enter the completion phase.” However, it was unclear what a “completion phase”
meant in technical terms. After showing the plant at Yongbyon to visiting American scientists in
November 2010, North Korea issued a statement saying that “a modern factory for uranium
enrichment equipped with thousands of centrifuges is operating to supply fuel” [to the light-water
reactor].48
U.S. Intelligence Assessments
A 2002 CIA report to Congress said, “In 2001, North Korea began seeking centrifuge-related
materials in large quantities. It also obtained equipment suitable for use in uranium feed and
withdrawal systems. North Korea’s goal appears to be a plant that could produce enough
weapons-grade uranium for two or more nuclear weapons per year when fully operational.”49 A
2002 unclassified CIA working paper on North Korea’s nuclear weapons and uranium enrichment
estimated that North Korea “is constructing a plant that could produce enough weapons-grade
uranium for two or more nuclear weapons per year when fully operational—which could be as
soon as mid-decade.”50 Such a plant would need to produce more than 50 kg of HEU per year,
requiring cascades of thousands of centrifuges.51
Questions have been raised about whether the 2002 estimates were accurate.52 In a hearing before
the Senate Armed Services Committee on February 27, 2007, Joseph DeTrani, the mission
manager for North Korea from the Office of the Director of National Intelligence and former
chief negotiator for the Six-Party Talks, was asked by Senator Jack Reed whether he had “any
further indication of whether that program has progressed in the last six years, one; or two, the
evidence—the credibility of the evidence that we had initially, suggesting they had a program
rather than aspirations?” DeTrani responded that “the assessment was with high confidence that,
indeed, they were making acquisitions necessary for, if you will, a production-scale program. And
we still have confidence that the program is in existence—at the mid-confidence level.” In a
clarification of his response, DeTrani issued a DNI press release that said there was a high level
of confidence in 2002 that North Korea had a uranium enrichment program, and “at least
moderate confidence that North Korea’s past efforts to acquire a uranium enrichment capability
46
http://www.kcna.co.jp/item/2009/200906/news13/20090613-10ee.html.
Hui Zhang, “Assessing North Korea’s Uranium Enrichment Capabilities,” Bulletin of the Atomic Scientists, June 28,
2009.
48
“North Korean paper reports plans for uranium enrichment,” BBC Monitoring Asia-Pacific, November 30, 2010.
49
Unclassified Report to Congress January-June 2002, Central Intelligence Agency, https://www.cia.gov/library/
reports/archived-reports-1/jan_jun2002.html#5
50
http://www.fas.org/nuke/guide/dprk/nuke/cia111902.html.
51
North Korea would first have to convert uranium “yellowcake” into uranium hexafluoride to feed into the
centrifuges. The centrifuges would “enrich” the uranium, or increase the portion of U-235. Weapons-grade enriched
uranium according to the IAEA needs to have an enrichment level of at least 20%. See CRS Report RL34234,
Managing the Nuclear Fuel Cycle: Policy Implications of Expanding Global Access to Nuclear Power, coordinated by
Mary Beth Nikitin.
52
Paul Kerr, “News Analysis: Doubts Rise on North Korea’s Uranium-Enrichment Program,” Arms Control Today,
April 2007, at http://www.armscontrol.org/act/2007_04/NewsAnalysis.asp.
47
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continue today.”53 Assistant Secretary of State Christopher Hill said in February 2007 that the
United States is not sure if North Korea has mastered “some considerable production techniques,”
although they have acquired some technology for an enrichment program.54
A DNI unclassified report of August 2007 stated,
We continue to assess with high confidence that North Korea has pursued efforts to acquire a
uranium enrichment capability, which we assess is intended for nuclear weapons. All
Intelligence Community agencies judge with at least moderate confidence that this past effort
continues. The degree of progress towards producing enriched uranium remains unknown,
however.55
In testimony to Congress on February 2008, Director of National Intelligence Michael McConnell
confirmed this assessment. The confidence level of these assessments may have changed because
of a decrease in international procurement by North Korea. Uranium enrichment-related imports
would be more easily detected by intelligence agencies than activities inside North Korea itself.
Uranium enrichment facilities can be hidden from aerial surveillance more easily than plutonium
facilities, making it more difficult for intelligence agencies to even detect—thus, “degree of
progress” in turning the equipment into a working enrichment program is “unknown.”
Furthermore, there are significant differences between assembling a small-scale centrifuge
enrichment program and operating a large-scale production plant, and reportedly little evidence of
procurement for a large-scale plant has emerged.56 Dr. Siegfried Hecker has assessed that it is
“highly likely that North Korea had a research and development uranium enrichment effort, but
there is little indication that they were able to bring it to industrial scale.”57
In 2007, North Korea gave the United States a sample of the aluminum tubing in an effort to
prove that it never intended to produce highly enriched uranium for weapons, and that the
imported materials were for conventional weapons or dual-use projects. However, when U.S.
scientists analyzed the aluminum tubing provided as sample “evidence,” they found traces of
enriched uranium on the tubing. Analysts argue that in addition to the possibility that this is proof
of a North Korean uranium enrichment program, it is also possible that the uranium traces could
have been on the tubing when North Korea received it.58
53
“There has been considerable misinterpretation of the Intelligence Community’s view of North Korean efforts to
pursue a uranium enrichment capability. The intelligence in 2002 was high quality information that made possible a
high confidence judgment about North Korea’s efforts to acquire a uranium enrichment capability. The Intelligence
Community had then, and continues to have, high confidence in its assessment that North Korea has pursued that
capability. We have continued to assess efforts by North Korea since 2002. All Intelligence Community agencies have
at least moderate confidence that North Korea’s past efforts to acquire a uranium enrichment capability continue
today.” ODNI News Release 04-07, March 4, 2007, at http://www.dni.gov/press_releases/20070304_release.pdf.
54
“Update on the Six Party Talks,” Brookings Institution, February 22, 2007, at http://www.brookings.edu/events/
2007/0222south-korea.aspx.
55
Unclassified Report to Congress on Nuclear and Missile Programs of North Korea, Office of the Director of National
Intelligence, August 8, 2007.
56
See David Albright, “North Korea’s Alleged Large-Scale Enrichment Plant: Yet Another Questionable Extrapolation
Based on Aluminum Tubes,” The Institute for Science and Security, February 23, 2007, at http://www.isis-online.org/
publications/dprk/DPRKenrichment22Feb.pdf.
57
Siegfried Hecker, “Denuclearizing North Korea,” Bulletin of the Atomic Scientists, May/June 2008.
58
Glenn Kessler, “Uranium Traces Found on N. Korean Aluminum Tubes,” Washington Post, December 21, 2007, at
http://www.washingtonpost.com/wp-dyn/content/article/2007/12/20/AR2007122002196_pf.html.
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In 2008, U.S. personnel found traces of highly-enriched uranium on the documents submitted as
part of North Korea’s nuclear declaration, raising new doubts about the extent of North Korea’s
uranium enrichment program.59 Ambassador Hill told Congress that North Korea included as part
of its June 2008 “declaration package” a letter that says that “they do not now and will not in the
future have a highly enriched uranium program.”60 However, the Section 721 Unclassified Report
to Congress covering the period January 1 to December 31, 2008, said that the IC had “increasing
concerns that North Korea has an ongoing covert uranium enrichment program.”
The Director of National Intelligence’s annual threat assessment to Congress in 2011 discussed
North Korea’s November 2010 unveiling of its uranium enrichment program:
We judge it is not possible the DPRK could have constructed the Yongbyon enrichment
facility and begun its operation, as North Korean officials claim, in such a short period of
time—less than 20 months—without having previously conducted extensive research,
development, testing, fabrication, and assembly or without receiving outside assistance.
Based on the scale of the facility and the progress the DPRK has made in construction, it is
likely that North Korea has been pursuing enrichment for an extended period of time. If so,
there is clear prospect that DPRK has built other uranium enrichment related facilities in its
territory, including likely R&D and centrifuge fabrication facilities, and other enrichment
facilities. Analysts differ on the likelihood that other production-scale facilities may exist
elsewhere in North Korea.61
The DNI’s 2012 threat assessment stated that North Korea’s announcement of a uranium
enrichment program in November 2010 confirmed long-standing intelligence assessments.62 The
intelligence community has not discussed detailed assessments of the uranium enrichment
program in open hearings.
Uranium Enrichment and Nuclear Negotiations
The uranium enrichment issue was central to denuclearization negotiations since October 2002,
when the Bush Administration accused North Korea of having a clandestine uranium enrichment
program. U.S. lead negotiator James Kelly told North Korean First Deputy Foreign Minister
Kang Sok-chu that the United States had evidence of a uranium enrichment program for nuclear
weapons in violation of the Agreed Framework and other agreements. James Kelly said that Kang
acknowledged the existence of such a program at that meeting. However, Kang later denied this,
and Foreign Minister Paek Nam Sun said that Kang had told Kelly that North Korea is “entitled”
to have such a program or “an even more powerful one” to deter a preemptive U.S. attack.63
After the November 2010 revelations of a small-scale centrifuge uranium enrichment facility,
negotiators have been faced with decisions over how to address this plant, which the North
59
Glenn Kessler, “New Data Found On North Korea’s Nuclear Capacity; Intelligence on Enriched Uranium Revives
Questions About Weapons,” The Washington Post, June 21, 2008.
60
Senate Armed Services Hearing on the North Korean Six-Party Talks and Implementation Activities, July 31, 2008.
61
James R. Clapper, Director of National Intelligence, Statement for the Record on the Worldwide Threat Assessment
of the U.S. Intelligence Community for the House Permanent Select Committee on Intelligence, February 10, 2011.
62
James R. Clapper, Director of National Intelligence, Unclassified Statement for the Record on the Worldwide Threat
Assessment of the US Intelligence Community for the Senate Select Committee on Intelligence, January 31, 2012.
63
Selig Harrison, “Did North Korea Cheat?” Foreign Affairs, vol. 84, no. 1, January/February 2005.
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North Korea’s Nuclear Weapons: Technical Issues
Koreans say is for the peaceful production of power plant fuel, and how to verify the
dismantlement of any other plants as part of any future denuclearization process.
U.S. official reactions downplayed North Korea’s new enrichment facility and related offers,
saying they are not surprising, and are not sufficient for a return to talks. For example, State
Department Spokesman P. J. Crowley said in late December 2010, “If they meet their
international obligations, take affirmative steps to reduce tensions in the region and take
affirmative steps to denuclearize, we will respond accordingly.”64 Neither the offer to sell the
fresh fuel or to invite international monitors to the uranium enrichment plant would have
demonstrated a commitment to denuclearization steps by North Korea, demanded by the U.S. and
South Korean governments as a condition for reconvening the Six-Party Talks. Officials from
both governments have said they want to avoid falling into the diplomatic “trap” of being drawn
into a lengthy negotiating process in which Pyongyang does not take concrete steps to
denuclearize. However, North Korea’s offers may have some intrinsic value on technical grounds:
removal of the fresh fuel could reduce the amount of ready material to produce plutonium if the 5
MWe reactor was restarted (it would take only six months to do so); the presence of international
inspectors at the newly built uranium enrichment site, depending on the degree of access given,
could shed light on the extent and type of technical capability of the North Korean enrichment
program. State Department spokesman Victoria Nuland announced on February 29, 2012, that
North Korea had agreed to a moratorium on enrichment activities at the Yongbyon site and a
return of international (IAEA) inspectors to verify the pause. North Korea had set up initial
meetings with IAEA officials. However, the February agreements collapsed after the North’s
attempted satellite launch in April 2012.
Nuclear Testing65
North Korea has technical and military reasons for testing an additional device or devices if it has
enough fissile material to do so. Analysts would look for two main indicators after a nuclear test
that could reveal information about North Korea’s nuclear weapons program. First, the yield of
the device, and secondly, the type of fissile material used. There are many uncertainties over
whether North Korea would test a plutonium device and deplete its shrinking plutonium stockpile
but advance the knowledge learned in earlier tests, whether it might pair a plutonium and HEU
device together in a test, or whether North Korea has enough HEU to test. Furthermore, it is not
guaranteed that the international community could discern the type of material used in a nuclear
test. The ability to do so would depend on what is vented from the test site and what is detected
through air sampling.66
64
“North Korea to Allow Nuclear Inspectors as Tension Eases, Richardson Says,” Bloomberg News, December 21,
2010.
65
See also CRS Report RL33548, Comprehensive Nuclear-Test-Ban Treaty: Background and Current Developments,
by Jonathan Medalia.
66
James Acton, “North Korea’s Latest Threat,” April 2012, http://carnegieendowment.org/2012/04/10/north-korea-slatest-threat/a7fk#6 and Hui Zhang, “Off Site Air Sampling Analysis and North Korean Nuclear Test,” Belfer Center,
http://belfercenter.ksg.harvard.edu/files/NKSampling_INMM07_Hui.pdf.
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The February 12, 2013, Nuclear Test
Observable test site activity at the Punggye-ri nuclear test site since mid-2012 led analysts to
believe North Korea was preparing the site for a third nuclear test. A nuclear test was carried out
on February 12, 2013. The North Korean official news agency announced a “successful”
underground nuclear detonation, and seismic monitoring systems measured a resulting earthquake
that was 5.1M in magnitude.67 Seismic waves were similar to the tests in 2006 and 2009. The
U.S. Director of National Intelligence issued a statement:
The U.S. Intelligence Community assesses that North Korea probably conducted an
underground nuclear explosion in the vicinity of P’unggye on February 12, 2013. The
explosion yield was approximately several kilotons. Analysis of the event continues.68
The South Korean Ministry of Defense estimated that the test yield was between 6 and 7
kilotons.69 North Korea claimed that the February 12, 2013, nuclear test was to develop a
“smaller and light” warhead. At a minimum, the test would likely contribute to North Korea’s
ability to develop a warhead that could be mounted on a long-range missile. It is unclear what
impact a third nuclear test would have on future negotiations, but it would make their success far
less likely, and the UN Security Council was discussing additional sanctions measures.
Observers are also waiting for evidence from test emissions that might show whether the North
Koreans tested a uranium or plutonium device. This information could help determine the type
and sophistication of the North Korean nuclear warhead design about which little is known. Two
U.S. experts, Hecker and Pabian, have assessed that North Korea used plutonium in both the 2006
and 2009 tests, and that without at least one additional successful plutonium test, the North would
not have confidence in its miniaturized plutonium design.70 Other experts believe North Korea
may choose to test highly enriched uranium-based devices. Testing of a uranium device might
indicate a clandestine supply of highly enriched uranium, potentially from an enrichment facility
in North Korea. If venting of the nuclear test site has occurred, air samples could indicate what
kind of material was used.
The May 25, 2009, Nuclear Test
The DPRK announced on May 25, 2009 that it had successfully conducted another underground
nuclear test. An official North Korean news release said that this test was “on a new higher level
in terms of its explosive power and technology of its control and the results of the test helped
satisfactorily settle the scientific and technological problems arising in further increasing the
power of nuclear weapons.” This may be a reference to design problems associated with the low
67
United States Geological Survey, http://earthquake.usgs.gov/earthquakes/eventpage/usc000f5t0#summary.
Statement by the Office of the Director of National Intelligence on North Korea’s Declared Nuclear Test on February
12, 2013, http://www.dni.gov/index.php/newsroom/press-releases/191-press-releases-2013/809-statement-by-theoffice-of-the-director-of-national-intelligence-on-north-korea’s
69
“ROK Defense Ministry Estimates DPRK’s Nuclear Device Yield of 6-7 Kilotons,” Yonhap News Agency, February
12, 2013.
70
Frank J. Pabian and Siegfried Hecker, “Contemplating a third nuclear test in North Korea,” Bulletin of the Atomic
Scientists, August 6, 2012.
68
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North Korea’s Nuclear Weapons: Technical Issues
yield of the 2006 test. A North Korean official statement had threatened on April 29, 2009, that it
would conduct “nuclear tests” to bolster its deterrent.71
The U.S. Geologic Survey registered an underground blast on May 25 with a seismic magnitude
of the event as 4.7 on the Richter scale.72 The Directorate of National Intelligence released a
statement on June 15 saying, “The U.S. Intelligence Community assesses that North Korea
probably conducted an underground nuclear explosion in the vicinity of P'unggye on May 25,
2009.”73 The explosion yield was first estimated to be approximately a “few” kilotons. In his
February 2012 annual threat to Congress, DNI Clapper said, “The North’s probable nuclear test
in May 2009 had a yield of roughly two kilotons TNT equivalent and was apparently more
successful than the 2006 test. These tests strengthen our assessment that North Korea has
produced nuclear weapons.”74
Open-source information is not available on the device’s design and how much nuclear material
was used. In contrast to 2006, no radioactive noble gases were detected by international
monitoring stations and no national governments have announced such data.75 It is possible that
North Korea may have been able to contain the release of these gases and particles from the test
site. This data can provide not only evidence of a test, but potentially also information on the type
of weapon detonated.76
The October 9, 2006, Nuclear Test77
The U.S. Director of National Intelligence confirmed that North Korea conducted an underground
nuclear explosion on October 9, 2006, in the vicinity of P’unggye.78 However, the sub-kiloton
yield of the test suggests that the weapon design or manufacturing process likely needs
improvement.79 North Korea reportedly told China before the test that it expected a yield of 4
kilotons (KT), but seismic data confirmed that the yield was less than 1 KT.80 Radioactive debris
indicates that the explosion was a nuclear test, and that a plutonium device was used.81 It is
71
“UNSC Urged to Retract Anti-DPRK Steps,” KCNA, April 29, 2009, http://www.kcna.co.jp/item/2009/200904/
news29/20090429-14ee.html.
72
http://earthquake.usgs.gov/eqcenter/recenteqsww/Quakes/us2009hbaf.php.
73
Statement by the Office of the Director of National Intelligence on North Korea’s Declared Nuclear Test on May 25,
2009, http://www.dni.gov/press_releases/20090615_release.pdf.
74
Annual Threat Assessment of the Director of National Intelligence for the Senate Select Committee on Intelligence,
January 31, 2012, at http://www.dni.gov/testimonies/20120131_testimony_ata.pdf.
75
http://www.ctbto.org/press-centre/highlights/2009/experts-sure-about-nature-of-the-dprk-event/.
76
See also “Factfile: underground nuclear testing,” BBC News, May 26, 2009, http://news.bbc.co.uk/2/hi/asia-pacific/
6033893.stm.
77
See also CRS Report RL33709, North Korea’s Nuclear Test: Motivations, Implications, and U.S. Options, by (name
redacted) and (name redacted), December 12, 2006.
78
“Analysis of air samples collected on October 11, 2006, detected radioactive debris which confirms that North Korea
conducted an underground nuclear explosion in the vicinity of P’unggye on October 9, 2006. The explosion yield was
less than a kiloton.” ODNI News Release No. 19-06, at http://www.dni.gov/announcements/20061016_release.pdf.
79
By comparison, a simple plutonium implosion device normally would produce a larger blast, perhaps 5 to 20 kilotons
(KT). The first nuclear tests conducted by other states range from 9 KT (Pakistan) to 60 KT (France), but tests by the
United States, China, Britain, and Russia were in the 20 KT range.
80
Mark Mazzetti, “Preliminary Samples Hint at North Korean Nuclear Test,” New York Times, October 14, 2006, at
http://www.nytimes.com/2006/10/14/world/asia/14nuke.html.
81
Thom Shanker and David Sanger, “North Korean fuel identified as plutonium,” New York Times, October 17, 2006,
(continued...)
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widely believed that the warhead design was an implosion device.82 Uncertainties remain about
when the plutonium used for the test was produced and how much plutonium was in the device,
although a prominent U.S. nuclear scientist has estimated that North Korea likely used
approximately 6 kg of plutonium for the test.83
The test’s low yield may not have been a complete failure. Another possibility is that the test’s
low yield was intentional—a sophisticated device designed for a Nodong medium-range missile.
Alternatively, a low yield could have been intended to avoid radioactive leakage from the test site
or to limit the amount of plutonium used.84 DNI Director Clapper in his 2012 annual threat
assessment to Congress called the 2006 test a “partial failure.”
Delivery Systems
Although former Defense Intelligence Agency (DIA) Director Lowell Jacoby told the Senate
Armed Services Committee in April 2005 that North Korea had the capability to arm a missile
with a nuclear device, Pentagon officials later backtracked from that assessment. A DNI report to
Congress says that “North Korea has short and medium range missiles that could be fitted with
nuclear weapons, but we do not know whether it has in fact done so.”85 North Korea has several
hundred short-range Scud-class and medium range No Dong-class ballistic missiles, and is
developing an intermediate range ballistic missile. The Taepo-Dong-2 that was tested
unsuccessfully in July 2006 would be able to reach the continental United States if it becomes
operational. DNI assessed in 2008 that the Taepo-Dong-2 has the potential capability to deliver a
nuclear-weapon-sized payload to the United States, but that absent successful testing the
likelihood of this is low.86 A launch of a Taepo-Dong 2 missile as part of a failed satellite launch
in April 2009 traveled further than earlier unsuccessful launches but still did not achieve a
complete test. An April 2012 launch of a Taepo-Dong 2 (called the Unha-3 by North Korea) also
failed in the first stage.87 The December 2012 launch of a Taepo-Dong 2 (Unha-3) was North
Korea’s first successful launch of a satellite into space. However, putting a satellite into orbit,
(...continued)
at http://www.nytimes.com/2006/10/17/world/asia/17diplo.html. A debate on this issue can be found in the November
2006 issue of Arms Control Today, at http://armscontrol.org/act/2006_11/tech.asp#Sidebar1.
82
Implosion devices, which use sophisticated lenses of high explosives to compress fissile material, are generally
thought to require testing, although the CIA suggested in 2003 that North Korea could validate a simple fission nuclear
weapons design using extensive high explosives testing. CIA response to questions for the record, August 18, 2003,
submitted by the Senate Select Committee on Intelligence, at http://www.fas.org/irp/congress/2003_hr/021103qfrcia.pdf.
83
Siegfried Hecker, “Report on North Korean Nuclear Program,” Center for International Security and Cooperation,
Stanford University, November 15, 2006.
84
Ibid. Also see Peter Hayes, Jungmin Kang, “Technical Analysis of the DPRK Nuclear Test,” Nautilus Institute,
October 22, 2006, http://www.nautilus.org/fora/security/0689HayesKang.html.
85
Unclassified Report to Congress on Nuclear and Missile Programs of North Korea, Office of the Director of National
Intelligence, August 8, 2007. Also see CRS Report RS21473, North Korean Ballistic Missile Threat to the United
States, by (name redacted).
86
Annual Threat Assessment of the Director of National Intelligence for the Senate Select Committee on Intelligence,
February 5, 2008, at http://www.dni.gov/testimonies/20080205_testimony.pdf.
87
“NORAD and USNORTHCOM Acknowledge Missile Launch,” NORAD News, April 12, 2012, Peterson Air Force
Base, Colorado.
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while moving North Korea technically to its goal, does not translate into a reliable missile.
Further testing would be required.
It is possible that Pakistani scientist A.Q. Khan may have provided North Korea the same
Chinese-origin nuclear weapon design he provided to Libya and Iran. Even though that design
was for an HEU-based device, it would still help North Korea develop a reliable warhead for
ballistic missiles—small, light, and robust enough to tolerate the extreme conditions encountered
through a ballistic trajectory. Learning more about what is needed for miniaturization of warheads
for ballistic missiles could have been the goal of North Korea’s testing smaller nuclear devices.88
Doctrine and Intent
U.S. officials in their threat assessments have described the North Korean nuclear capabilities as
being more for deterrence, international prestige, and coercive diplomacy than for war fighting,
and assess that Pyongyang most likely “would consider using nuclear weapons only under narrow
circumstances.” The Director of National Intelligence said in early 2012 that “we also assess,
albeit with low confidence, Pyongyang probably would not attempt to use nuclear weapons
against US forces or territory, unless it perceived its regime to be on the verge of military defeat
and risked an irretrievable loss of control.”89
Statements by North Korean officials emphasize that moves to expand their nuclear arsenal are in
response to perceived threats by the United States against the North Korean regime.90 Nuclear
weapons also give North Korea leverage in diplomatic negotiations, and threatening rhetoric
often coincides with times of crisis or transitions in negotiations. In January 2008, a North
Korean media report stated that the country “will further strengthen our war deterrent capabilities
in response to U.S. attempts to initiate nuclear war,” to express its displeasure that it had not yet
been removed from the U.S. terrorism list.91 Statements from Pyongyang in January 2009 may
also be part of a strategy to increase leverage in nuclear talks,92 or could indicate an increasing
role for the North Korean military in nuclear policy making.93 A spokesman for North Korea’s
General Staff said on April 18, 2009, that the revolutionary armed forces “will opt for increasing
the nation’s defense capability including nuclear deterrent in every way.”94 At the same time, the
DPRK issues periodic statements, such as its 2010 New Year’s address stating its dedication to
achieving a nuclear-free Korean Peninsula through negotiations.
88
“Technical Perspective on North Korea’s Nuclear Test: A Conversation between Dr. Siegfried Hecker and Dr. GiWook Shin,” Stanford University website, October 10, 2006, at http://aparc.stanford.edu/news/
technical_perspective_on_north_koreas_nuclear_test_a_conversation_between_dr_siegfried_hecker_and_dr_giwook_s
hin_20061010//.
89
Annual Threat Assessment of the Director of National Intelligence for the Senate Select Committee on Intelligence,
January 31, 2012, at http://www.dni.gov/testimonies/20120131_testimony_ata.pdf.
90
See, for example, North Korea’s statement of February 10, 2005, at http://news.bbc.co.uk/2/hi/asia-pacific/
4252515.stm.
91
“North Korea says nuclear declaration submitted,” Reuters, January 4, 2008.
92
Blaine Harden, “With Obama in the White House, North Korea Steps Up Big Talk,” Washington Post, February 3,
2009.
93
See “North Korea” section of CRS Report R40439, Nuclear Weapons R&D Organizations in Nine Nations,
coordinated by Jonathan Medalia.
94
“DPRK military warns against sanctions for rocket launch,” Xinhua, April 18, 2008.
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In May 2012, North Korea changed its constitution to say that it was a “nuclear-armed state.”95
On April 1, 2013, its party congress adopted the “Law on Consolidating Position of Nuclear
Weapons State.” The official media (KCNA) summarized the law as saying that nuclear weapons
“serve the purpose of deterring and repelling the aggression and attack of the enemy against the
DPRK and dealing deadly retaliatory blows at the strongholds of aggression until the world is
denuclearized.” The statement also said that the “nuclear weapons of the DPRK can be used only
by a final order of the Supreme Commander of the Korean People’s Army to repel invasion or
attack from a hostile nuclear weapons state and make retaliatory strikes. The DPRK shall neither
use nukes against the non-nuclear states nor threaten them with those weapons unless they join a
hostile nuclear weapons state in its invasion and attack on the DPRK.” This is the most detailed
statement on North Korean nuclear use policies to date.
Steps Toward Denuclearization Under the
Six-Party Talks (2005-2009)
In September 2005, North Korea agreed to abandon “all nuclear weapons and existing nuclear
programs,” but implementation of this goal was stalled.96 The October 9, 2006, nuclear test is
seen as a catalyst in uniting the other members of the Six-Party Talks to toughen their stance
towards North Korea, and as a turning point in Pyongyang’s attitude. U.N. Security Council
Resolution 1718 calls on North Korea to abandon its nuclear weapons in a “complete, verifiable,
and irreversible manner.”97 In February 2007, as part of implementation of the September 2005
Joint Statement, North Korea committed to disable all nuclear facilities and provide a “complete
and correct” declaration of all its nuclear programs.98
Disablement
The October 2007 Six-Party joint statement said the United States would lead disablement
activities and provide the initial funding for those activities.99 Disablement indicates a physical
measure to make it difficult to restart operation of a facility while terms are being worked out for
its eventual dismantlement. U.S. officials said that their aim was a disablement process that
would require a 12-month time period to start up the facility again.100 The Six Parties agreed to 11
discrete steps to disable the three main Yongbyon facilities related to North Korea’s plutonium
program (nuclear fuel fabrication plant, plutonium reprocessing plant, and 5-megawatt
experimental nuclear power reactor).101 The disablement process began in early November 2007
95
“New N. Korea constitution proclaims nuclear status,” Agence France Presse, May 31, 2012.
Joint Statement of the Fourth Round of Six Party Talks, Beijing, September 19, 2005, at http://www.state.gov/r/pa/
prs/ps/2005/53490.htm.
97
United Nations Security Council Resolution 1718, October 14, 2006, at http://daccessdds.un.org/doc/UNDOC/GEN/
N06/572/07/PDF/N0657207.pdf?OpenElement.
98
“Denuclearization Action Plan,” February 13, 2007, at http://merln.ndu.edu/archivepdf/northkorea/state/80479.pdf.
99
Second Phase Actions for the Implementation of the September 2005 Joint Statement, October 3, 2007, at
http://www.state.gov/r/pa/prs/ps/2007/oct/93223.htm.
100
On-the-Record-Briefing, U.S. Assistant Secretary of State Christopher Hill, October 3, 2007, at
http://www.state.gov/p/eap/rls/rm/2007/93234.htm.
101
“North Korea ‘Agrees to Nuclear Disablement Procedure,’” Chosun Ilbo, October 27, 2007.
96
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and continued through April 2009. The most time-consuming step was the removal of the
irradiated fuel from the reactor to storage in an adjacent cooling pond.102 A reported 8 out of 11
steps were completed (see Table 2).103
Table 2. Disablement Steps at Yongbyon, DPRK
Step
Facility
Status
Discharge of 8000 spent fuel rods
to the spent fuel pool
5-megawatt reactor
6,400 completed as of April 2009
Removal of control rod drive
mechanisms
5-megawatt reactor
To be done after spent fuel removal
completed
Removal of reactor cooling loop
and wooden cooling tower
interior structure
5-megawatt reactor
Tower demolished June 26, 2008
Disablement of fresh fuel rods
Fuel fabrication facility
Not agreed to by North Korea;
consultations held Jan. 2009 with
South Korea on possibility of
purchase
Removal and storage of three
uranium ore concentrate dissolver
tanks
Fuel fabrication facility
Completed
Removal and storage of seven
uranium conversion furnaces,
including storage of refractory
bricks and mortar sand
Fuel fabrication facility
Completed
Removal and storage of both
metal casting furnaces and vacuum
system, and removal and storage
of eight machining lathes
Fuel fabrication facility
Completed
Cut cable and remove drive
mechanism associated with the
receiving hot cell door
Reprocessing facility
Completed
Cut two of four steam lines into
reprocessing facility
Reprocessing facility
Completed
Removal of drive mechanisms for
the fuel cladding shearing and
slitting machines
Reprocessing facility
Completed
Removal of crane and door
actuators that permit spent fuel
rods to enter the reprocessing
facility
Reprocessing facility
Completed
Source: “North Korean Disablement Actions,” Arms Control Today, October 2008; “Disablement Actions,”
National Committee on North Korea website; Siegfried Hecker, “Denuclearizing North Korea,” Bulletin of the
Atomic Scientists, May/June 2008.
102
David Albright and Paul Brannan, “Disabling DPRK Nuclear Facilities,” United States Institute of Peace Working
Paper, October 23, 2007.
103
See charts at “North Korean Disablement Actions,” Arms Control Today, October 2008; “Disablement Actions,”
National Committee on North Korea website.
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North Korea periodically slowed the pace of spent fuel rod removal at Yongbyon to show its
displeasure over other aspects of the Six-Party agreements.104 For example, in June 2008,
Pyongyang said that while 80% of the disablement steps had been completed, only 36% of energy
aid had been delivered.105 North Korea again delayed disablement work in August, September,
and October 2008, and those instances appear to have been linked to disputes over when the
United States would remove the DPRK from its State Sponsors of Terrorism List and negotiations
over verification measures. After the United States removed the SST designation, disablement
work resumed in October 2008, and continued until North Korea halted the process in April 2009.
The steps that were not completed in disabling the Yongbyon facilities as part of phase 2 of the
Six-Party Talks are completing the removal of the spent fuel rods from the 5 megawatt reactor;
removing the control rod drive mechanism (after all rods are removed); and disabling or
removing from the country the fresh fuel rods at the site. As of early April 2009, approximately
80% or 6,400 of the 8,000 spent fuel rods had been moved from the reactor to the cooling
pond.106 Pyongyang subsequently issued statements saying it had itself removed the remaining
fuel rods from the reactor and completed reprocessing all 8,000 spent fuel rods by August
2009.107
In addition, North Korea possesses 2,400 5-MWt fresh fuel rods and 12,000 50-MWt fresh fuel
rods in storage at Yongbyon. A technical delegation from South Korea visited the facility in
January 2009 to consider possibilities for removing the fuel rods. Another option discussed was to
bend them so they could not be readily used in the reactor.108 It is not clear whether North Korea
had agreed to disablement or removal of the fresh fuel, and then balked, or whether it never had
agreed to this measure. North Korea told visiting unofficial American delegations in late 2010
that the North would consider shipping out (and selling) the 12,000 fresh fuel rods, most likely to
South Korea, if the United States reaffirmed a 2000 Joint Statement which said the United States
held no hostile intent toward the North.109
Reversing Disablement
The North Korean Foreign Ministry said on April 25, 2009, that it had restarted its reprocessing
facility, but there has been no way to independently verify this. North Korea said in November
2009 that it had reprocessed the 8,000 spent fuel rods in its possession by the end of August.
The extent to which the Yongbyon facilities had been disabled was first tested in September 2008
when North Korea halted international monitoring at the reprocessing facility, moved some
equipment out of storage, and threatened to begin reprocessing again.110 This temporary reversal
was corrected and equipment moved back to storage by November 2008. Taking into account the
104
“N. Korea ‘Slowing Disablement of Nuclear Facilities,” Chosun Ilbo, January 29, 2008.
Lee Chi-dong, “N Korea Complains About Slow Provision of Energy Aid,” Yonhap News, June 5, 2008.
106
“N. Korea can produce plutonium for 1.5 bombs in 6 months: expert,” Kyodo News, April 25, 2009.
107
Kim So-hyun, “N.K. says it reprocessed 8,000 spent fuel rods,” The Korea Herald, November 4, 2009.
108
“MOFAT Reveals North Korean Fuel Rod Images,” Daily North Korea, February 4, 2009. http://www.dailynk.com/
english/read.php?cataId=nk03100&num=4516.
109
John Pomfret, “North Korea suggests discarding one of its nuclear arms programs in deal,” The Washington Post,
November 22, 2010.
110
IAEA Press Release, “IAEA Removes Seals at Yongbyon,” September 24, 2008.
105
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need to test the facility (e.g., for leaks and cracks in the piping) and introduce chemicals, experts
estimated that restarting the reprocessing plant could take approximately six to eight weeks,
although this timeline might be shorter since some initial work may have been done in September
2008. It would then take approximately three to four months to reprocess the spent fuel rods now
in storage at Yongbyon, resulting in 7 kg to 8 kg of plutonium. This would be enough for at least
one nuclear weapon.111 According to reports, disablement was limited to the “front-end,” where
spent fuel is loaded, at the reprocessing facility for technical reasons related to the safe disposal
of the high-level waste in the facility.112
In order to produce additional plutonium, the North Koreans would need to restore their 5-MWt
reactor or build a new reactor. Timelines for restoring the 5-MWt reactor are uncertain, although
experts estimate between six months and one year. Rebuilding the cooling tower, which was
destroyed in June 2008, could take approximately six months, but other venting solutions for the
reactor could be possible. Additionally, this aging reactor may be in need of additional parts or
repair. The fuel fabrication facility would have to be restored to produce additional fuel. Former
Director of the Los Alamos National Laboratories Siegfried Hecker has said that while significant
work is needed to do so, North Korea could restore operations at the 5 megawatt reactor and fuel
fabrication facility without foreign equipment or materials, and could do so in approximately six
months. After the facilities were operating, they could produce approximately 6 kg of plutonium
per year.113 Dr. Hecker confirmed this estimate again after his visit to North Korea in November
2010.114 Significant future growth in North Korea’s arsenal would be possible only if larger
reactors were completed and operating, and would also depend on any progress in the reported
uranium enrichment program.
Declaration
The required content of a “complete and correct” declaration as promised under the Six-Party
negotiations evolved over time. Bush Administration officials in fall 2007 said they expected the
declaration to include a full declaration of the separated weapons-grade plutonium that has
already been produced, as well as full disclosure of uranium enrichment activities.115 The North
Korean Foreign Ministry said on January 4, 2008, that it had notified the United States of the
content of its declaration in November 2007. However, Assistant Secretary Hill said that the two
sides had discussed what was expected to be in a declaration, and “it was clearly not a complete
and correct declaration.”116 At that time, North Korea reportedly suggested it would declare 30 kg
of separated plutonium in its declaration, a lower number than U.S. officials have alluded to (see
111
Peter Crail, “North Korea Moves to Restart Key Nuclear Plant,” Arms Control Today, October 2008.
For a discussion of the pro’s and con’s see sidebar “A Diplomatic and Technological Cocktail,” Bulletin of the
Atomic Scientists, May/June 2008, p.49.
113
“North Korea can produce plutonium for 1.5 bombs in 6 months,” Japan Economic Newswire, April 25, 2009.
114
Siegfried Hecker, “A Return Trip to North Korea’s Yongbyon Nuclear Complex,” Center for International Security
and Cooperation, Stanford University, November 20, 2010. http://iis-db.stanford.edu/pubs/23035/
HeckerYongbyon.pdf.
115
On-The-Record Briefing: Assistant Secretary of State for East Asian and Pacific Affairs and Head of the U.S.
Delegation to the Six-Party Talks Christopher R. Hill, October 3, 2007, at http://www.state.gov/p/eap/rls/rm/2007/
93234.htm.
116
Joint Press Availability, Assistant Secretary of State Christopher R. Hill, January 7, 2008. http://www.state.gov/p/
eap/rls/rm/2008/01/98756.htm.
112
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above) but in the range of some analyses.117 The United States has said that “materials, facilities
and programs” need to be included in a declaration. In addition to plutonium stocks, North Korea
agreed to “address concerns about a uranium enrichment program but denies that it has one” (see
below). Other outstanding issues are nuclear proliferation activities and warhead information.
North Korea has said it would not include warhead information at this stage. Once the original
December 31 deadline for submission of the declaration had passed, U.S. officials emphasized
that the completeness of the document was more important than its timing. U.S. officials also
made statements in early 2008 that removal from sanctions lists would only happen after a
complete declaration was submitted to the six parties.
According to press reports,118 at a bilateral meeting in Singapore in April 2008, the United States
and North Korea agreed to a formulation in which North Korea would include its plutonium
production activities in a formal declaration, and the enrichment and proliferation issues would be
dealt with separately in a secret side agreement in which North Korea would “acknowledge” the
U.S. concerns over North Korean proliferation to Syria without confirming or denying them. This
agreement is also supposed to have included a pledge by North Korea that it would not engage in
any future nuclear proliferation. Administration officials in spring 2008 emphasized that ending
plutonium production and tallying the plutonium stockpile were the highest priorities. However,
concerns were raised in the Congress and elsewhere by those skeptical of this approach, with
some observers wanting assurance that the North Korean declaration of its plutonium stockpile
would be adequately verified before the United States removed them from the State Sponsors of
Terrorism List.
On May 8, 2008, North Korean officials gave State Department Korean Affairs Director Sung
Kim approximately 19,000 pages of documentation related to its nuclear program. According to a
State Department fact sheet, the documents consist of operating records for the five-megawatt
reactor [5-MW(e)] and fuel reprocessing plant at the Yongbyon nuclear complex, dating back to
1986. They reportedly include reactor operations and information on all three reprocessing
campaigns undertaken by North Korea.119 As referenced above, press reports indicated that U.S.
personnel had found traces of highly-enriched uranium on these documents, raising new doubts
about the extent of North Korea’s uranium enrichment program at a sensitive juncture in the
negotiations.120
On June 26, 2008, North Korea submitted a declaration of its nuclear programs to China, the
chair of the Denuclearization Working Group. Ambassador Christopher Hill said in testimony to
Congress that the “declaration package” addresses “its plutonium program, and acknowledged
our concerns about the DPRK’s uranium enrichment and nuclear proliferation activities,
117
David Albright, Paul Brannan, and Jacqueline Shire, “North Korea’s Plutonium Declaration: A Starting Point for an
Initial Verification Process,” The Institute for Science and International Security, January 10, 2008. http://www.isisonline.org/publications/dprk/NorthKoreaDeclaration10Jan2008.pdf.
118
See, for example, Helene Cooper, “Past Deals by N. Korea May Face Less Study,” The New York Times, April 18,
2008. http://www.nytimes.com/2008/04/18/washington/18diplo.html?_r=2&adxnnl=1&oref=slogin&ref=world&
adxnnlx=1208545358-9gpsLj35wtiPmoT8RHM6mQ and Glenn Kessler, “U.S. Ready to Lift Sanctions on North
Korea,” The Washington Post, April 11, 2008. http://www.washingtonpost.com/wp-dyn/content/article/2008/04/10/
AR2008041004082.html?nav=emailpage.
119
“Update on the Six-Party Talks,” State Department Fact Sheet, May 10, 2008. http://www.state.gov/r/pa/prs/ps/
2008/may/104558.htm.
120
Glenn Kessler, “New Data Found On North Korea’s Nuclear Capacity; Intelligence on Enriched Uranium Revives
Questions About Weapons,” The Washington Post, June 21, 2008.
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specifically with regard to Syria.”121 Press reports have said that North Korea submitted a list of
nuclear sites and declared 37 kg of plutonium in the 60-page document. The confidential message
acknowledging U.S. concerns about uranium enrichment and proliferation activities was received
days earlier.122 In response, also on June 26, 2008, President Bush announced that the Trading
with the Enemy Act (TWEA) would no longer apply to North Korea and notified Congress of his
intent to remove North Korea’s designation as a State Sponsor of Terrorism (SST) after the
required 45-day wait period.123 The day after the declaration was submitted the U.S. assisted
North Korea in destroying the cooling tower at the 5-megawatt reactor at Yongbyon. Subsequent
verification issues are discussed below.
Verification
IAEA inspectors returned to North Korea in July 2007 to monitor and verify the shut-down,
install seals, and monitor facilities at the Yongbyon nuclear complex, and had a continuous
presence there until mid-April 2009.124 In his September 10, 2007, statement to the IAEA Board
of Governors, Director General Mohamed ElBaradei stated that the IAEA was able to verify the
shutdown of nuclear facilities, including the nuclear fuel fabrication plant, radio-chemical
laboratory (reprocessing plant), and the 5 MWe experimental nuclear power reactor. Inspectors
were also monitoring the halt in construction of the 50-megawatt nuclear power plant at
Yongbyon and the 200-megawatt nuclear power plant in Taechon.125 The United States has
contributed $1.8 million as the U.S. voluntary contribution and Japan has contributed $500,000 to
the IAEA for their work in North Korea.126 In the future, the IAEA may be called on to
investigate North Korea’s past nuclear program in addition to monitoring activities; however, to
date, its role was limited to monitoring the shut-down of Yongbyon facilities. The IAEA’s role in
disablement and future dismantlement efforts was not clearly determined. Some analysts
recommended an observer role for the IAEA during disablement steps and continued IAEA
monitoring to boost international confidence in the process.127 The United States and North Korea
reportedly agreed on a “consultative and support” role for the IAEA in future verification in
October 2008.128
After IAEA inspectors were expelled from North Korea in 2002, information about North Korea’s
nuclear weapons production depended on remote monitoring and defector information, with
121
Statement of Christopher R. Hill, Assistant Secretary of State, Bureau of East Asian and Pacific Affairs, U.S.
Department of State, to the Senate Committee on Armed Services, July 31, 2008.
122
Glenn Kessler, “Message to US Preceded North Korean Nuclear Declaration,” The Washington Post, July 2, 2008.
123
http://www.whitehouse.gov/news/releases/2008/06/20080626-4.html; http://www.state.gov/r/pa/prs/ps/2008/jun/
106281.htm.
124
“IAEA Team Confirms Shut Down of DPRK Nuclear Facilities,” IAEA press release, July 18, 2007, at
http://www.iaea.org/NewsCenter/PressReleases/2007/prn200712.html.
125
GOV/2007/45-GC(51)/19, August 17, 2007.
126
Statement of Christopher R. Hill Assistant Secretary, Bureau of East Asian and Pacific Affairs, Department of State
before the House Committee on Foreign Affairs, Subcommittee on Asia, the Pacific and the Global Environment and
Subcommittee on Terrorism, Nonproliferation and Trade, Joint Hearing on the North Korea Six-Party Process, October
25, 2007.
127
North Korea reportedly did not want the IAEA involved and wanted the United States to do the disabling. Albright
and Brannan, ibid.
128
“U.S.-North Korea Understandings on Verification,” October 11, 2008. http://2001-2009.state.gov/r/pa/prs/ps/2008/
oct/110924.htm.
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mixed results. Satellite images correctly indicated the start-up of the 5 MWe reactor, but gave no
details about its operations. Satellites also detected trucks at Yongbyon in late January 2003, but
could not confirm the movement of spent fuel to the reprocessing plant;129 imagery reportedly
detected activity at the reprocessing plant in April 2003, but could not confirm large-scale
reprocessing;130 and satellite imagery could not peer into an empty spent fuel pond, which was
shown to U.S. visitors in January 2004. North Korean officials stated in 2004 that the
reprocessing campaign was conducted continuously (four six-hour shifts). U.S. efforts to detect
Krypton-85 (a by-product of reprocessing) reportedly suggested that some reprocessing had taken
place, but were largely inconclusive. Even U.S. scientists visiting Pyongyang in January 2004
could not confirm North Korean claims of having reprocessed the spent fuel or that the material
shown was in fact plutonium. These are some of the uncertainties verification measures will seek
to answer.
Verification received increased attention in the Six-Party process beginning in spring 2008.
Statements made by President Bush and Secretary of State Rice in June 2008 further
demonstrated that the U.S. Administration was linking SST removal with progress on verification
issues.131 U.S. officials have said there have been spoken agreements with the North Koreans
saying that the only way the declaration can be deemed “complete and correct” is if it verifiable.
The State Department said in a June 26 fact sheet that by submitting the declaration, North Korea
had “begun to fulfill its declaration commitment.” The fact sheet also stated that a comprehensive
verification regime would include “short notice access to declared or suspect sites related to the
North Korean nuclear program, access to nuclear materials, environmental and bulk sampling of
materials and equipment, interviews with personnel in North Korea, as well as access to
additional documentation and records for all nuclear related facilities and operations.” It also said
that the actual rescission of North Korea’s designation as a State Sponsor of Terrorism will occur
only after “the Six Parties reach agreement on acceptable verification principles and an
acceptable verification protocol; the Six Parties have established an acceptable monitoring
mechanism; and verification activities have begun.”132
On July 12, 2008, the Six Parties agreed unanimously to principles for a “verification
mechanism” for the denuclearization of the Korean Peninsula, to be detailed by the
denuclearization working group.133 Thereafter, U.S. negotiators submitted a proposed verification
protocol to North Korea called the “Verification Measures Discussion Paper” which outlined
extensive measures to verify all aspects of North Korea’s nuclear programs, including plutonium
production, uranium enrichment, weapons, weapons production and testing, and proliferation
activities.134 North Korea reportedly submitted a counter-proposal that objected to provisions
related to inspections at undeclared facilities and the taking of samples.
129
“Reactor Restarted, North Korea Says,” Washington Post, February 6, 2003.
“US Suspects North Korea Moved Ahead on Weapons,” New York Times, May 6, 2003.
131
“President Bush Discusses North Korea,” White House press release, June 26, 2008; Condoleezza Rice, “U.S.
Policy Toward Asia,” Heritage Foundation speech, June 18, 2008.
132
“North Korea: Presidential Action on State Sponsor of Terrorism (SST) and the Trading with the Enemy Act
(TWEA),” State Department Fact Sheet, June 26, 2008. http://www.state.gov/r/pa/prs/ps/2008/jun/106281.htm.
133
Press Communique of the Heads of Delegation Meeting of the Sixth Round of the Six-Party Talks, Beijing, July 12,
2008. http://www.mofa.go.jp/region/asia-paci/n_korea/6party/press0807.html.
134
This paper was made public by the Washington Post. Glenn Kessler, “Far-Reaching U.S. Plan Impaired North
Korea Deal,” The Washington Post, September 26, 2008.
130
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The 45-day wait period for the SST List removal ended on August 11, 2008, but the
Administration did not take action. On August 26, the North Korean news agency announced it
had suspended disablement activities at Yongbyon as of August 14 since the United States had not
removed it from the terrorism list. The North Korean Foreign Ministry statement said that the
agreement had been to delist North Korea once it had submitted a declaration of its nuclear
programs, not once verification measures had been agreed upon. It said, “As far as the
verification is concerned, it is a commitment to be fulfilled by the six parties at the final phase of
the denuclearization of the whole Korean Peninsula according to the September 19 joint
statement.... All that was agreed upon at the present phase was to set up verification and
monitoring mechanisms within the framework of the six parties.”135 The statement also threatened
to restore facilities at Yongbyon.
On Monday, September 22, 2008, North Korea asked the International Atomic Energy Agency
(IAEA) personnel monitoring the shut-down of facilities at the Yongbyon nuclear complex to
remove the seals and surveillance equipment from the plutonium reprocessing plant. North Korea
informed the IAEA that inspectors would no longer have access to that facility. IAEA inspectors
and U.S. Department of Energy personnel located at Yongbyon were not expelled from the
Yongbyon site, and other monitoring and inspection activities related to disablement continued.
However, North Korea told the IAEA that it planned to “introduce nuclear material to the
reprocessing plant in one week’s time.”136
These actions were reversed when, in early October, the United States and North Korea agreed on
a Averification mechanism@ to determine the accuracy of the DPRK’s declaration of its plutonium
production. Ambassador Hill traveled to Pyongyang October 2-3 for further bilateral talks on the
verification agreement. As a result of these talks, the United States and DPRK reached agreement
on verification measures. Although the document has not yet been made public, according to
State Department officials North Korea has agreed to the United States taking samples out of
country for review; visits to all declared sites and to undeclared sites by mutual consent;
participation of South Korea and Japan in verification; and a consultative role for the IAEA.137
They also agreed that “all measures contained in the Verification Protocol will apply to the
plutonium-based program and any uranium enrichment and proliferation activities.” According to
the State Department’s fact sheet on the agreement, the measures are “codified in a joint
document between the United States and North Korea and certain other understandings.” Many
observers interpret “other understandings” as referring to verbal agreements or separate
documents, but neither the United States nor North Korea has made this clear. The United States
removed North Korea from the State Sponsors of Terrorism List on October 11.
Then-presidential candidate Barack Obama issued a statement after the October 11, 2008, SST
list removal that emphasized strong verification measures:
If North Korea refuses to permit robust verification, we should lead all members of the Six
Party talks in suspending energy assistance, re-imposing sanctions that have recently been
waived, and considering new restrictions. Our objective remains the complete and verifiable
135
“Foreign Ministry’s Spokesman on DPRK’s Decision to Suspend Activities to Disable Nuclear Facilities,” KCNA,
August 27, 2008. http://www.kcna.co.jp/index-e.htm.
136
http://www.iaea.org/NewsCenter/PressReleases/2008/prn200813.html.
137
See October 11, 2008, State Department Press Statement http://2001-2009.state.gov/r/pa/prs/ps/2008/oct/
110924.htm and Fact Sheet http://2001-2009.state.gov/r/pa/prs/ps/2008/oct/110924.htm.
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elimination of North Korea’s nuclear weapons programs. This must include getting clarity on
North Korea’s efforts to enrich uranium and its proliferation of nuclear technology abroad.138
Key concerns about the details of the tentative verification agreement as well as whether North
Korea had actually agreed to the provisions surfaced soon after the announcement. For example,
while State Department officials said that North Korea agreed to removal of samples from the
country for analysis, North Korean statements in press reports contradicted this.139 The Six Parties
were unable to reach agreement on a codified version of the verification measures in their
December 2008 meeting, as North Korea appeared to reject inclusion of sampling provisions.
As described above, verification and monitoring activities in North Korea ended when
Pyongyang asked U.S. and international inspectors to leave the country on April 14, 2009.140
North Korea reportedly told Bill Richardson in December 2010 that it would allow IAEA
inspectors into the country to verify that the uranium enrichment plant built at Yongbyon was for
peaceful purposes and was not producing highly enriched uranium (which could be used for
weapons).141
Future Considerations
The DPRK committed in 2005 to abandoning “all nuclear weapons and existing nuclear
programs” and to returning to the Non-Proliferation Treaty and IAEA safeguards at an early
date.142 If the DPRK decides to return to the Six-Party Talks and uphold these commitments, there
will be a number of issues that have not yet been resolved.
The next stage, after disablement, was to have been the decommissioning and dismantlement of
the weapons production facilities. The terms for this work still need to be negotiated. This stage
may include a return of IAEA monitoring of nuclear material stocks (including weapons-usable
separated plutonium) and verification of actual weapons dismantlement. The question of
dismantling North Korea’s nuclear warheads has not yet been addressed directly, although the
September 2005 joint statement commits North Korea to abandon all nuclear weapons. Critics
have raised concerns about the lack of clear verification provisions for these steps and the
omission of specific references to key issues such as fissile materials, warheads, the reported
uranium enrichment program, the nuclear test site, and nuclear proliferation activities and history
(such as possible nuclear transfers to Syria).
Some analysts have proposed that the United States should be ready to implement cooperative
threat reduction (CTR)-style programs in North Korea, as were created for the former Soviet
Union.143 These might include the redirection of North Korean nuclear weapon scientists to
138
Statement of Senator Barack Obama on the Agreement with North Korea, October 11, 2008.
“SKorea to press for sampling at NKorean nuke plants,” Agence France Presse, November 14, 2008.
http://news.yahoo.com/s/afp/20081113/wl_asia_afp/nkoreanuclearweaponsskoreaus.
140
“IAEA Inspectors Asked to Leave the Democratic People’s Republic of Korea,” IAEA Press Release, April 14,
2009, http://www.iaea.org/NewsCenter/PressReleases/2009/prn200903.html.
141
Chris Buckley, “North Korea to allow in IAEA inspectors—Richardson,” Reuters, December 21, 2010.
142
http://2001-2009.state.gov/r/pa/prs/ps/2005/53490.htm.
143
Joel Wit, Jon Wolfsthal, Choong-suk Oh, “The Six Party Talks and Beyond: Cooperative Threat Reduction in North
Korea,” CSIS Press, December 2005. http://www.csis.org/media/csis/pubs/051216_ctr.pdf.
139
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peaceful work.144 North Korean officials have said that they are interested in eventually
reorienting the Yongbyon workforce to the peaceful use of nuclear energy.145 This could include
research, medical and industrial applications, and not necessarily a nuclear power program.
An agreement reached in February 2012 (described below) gave priority to moratoria on key
weapons development activities—nuclear testing, long-range missile testing, uranium
enrichment—in an effort to slow North Korea’s progress and gather information (through
inspections), and as a precondition to returning to the negotiating table. That agreement collapsed,
but future talks could explore similar measures as well as more permanent solutions, which would
most likely include opening up to verification any additional uranium enrichment facilities,
dismantlement of weapons material production facilities, and verification of past plutonium
production and stocks at a minimum. North Korea has been reluctant to agree to this level of
transparency in the past.
The Leap Day Agreement
A set of February 2012 agreements collapsed after North Korea violated its missile moratorium
with a failed satellite launch in April. The United States and North Korea on February 29, 2012,
had separately announced agreement on a number of steps that could have paved the way for a
return to denuclearization under the Six-Party Talks process.146 Efforts toward dismantling North
Korea’s nuclear weapons program under the Six-Party Talks had been stalled since the spring of
2009 when North Korea conducted a second nuclear test. 147
In the February 29, 2012, announcements, North Korea committed to
•
a long-range missile testing moratorium,
•
a nuclear testing moratorium,
•
a moratorium on enrichment activities at Yongbyon, and
•
a return of IAEA inspectors to the Yongbyon nuclear facilities.
The United States announced that the two countries would hold further talks to finalize details on
a “targeted U.S. program consisting of an initial 240,000 metric tons of nutritional assistance with
the prospect of additional assistance based on continued need.”148 The U.S. statement also
emphasized several wider security issues, such as its continued commitment to the 1953 armistice
agreement and desire to increase people-to-people contacts with the DPRK.
144
David Albright, “Phased International Cooperation with North Korea’s Civil Nuclear Programs,” Institute for
Science and International Security, March 19, 2007. http://www.isis-online.org/publications/dprk/CivilNuclearNK.pdf.
145
“North Korea and Its Nuclear Program—A Reality Check,” A Report to Members of the Committee on Foreign
Relations, United States Senate, October 2008, S. Prt. 110-50.
146
“U.S.-DPRK Bilateral Discussions,” State Department Press Statement, February 29, 2012. http://www.state.gov/r/
pa/prs/ps/2012/02/184869.htm.
147
See CRS Report R41259, North Korea: U.S. Relations, Nuclear Diplomacy, and Internal Situation, by (name
redacted) and (name redacted).
148
For details see CRS Report R40095, Foreign Assistance to North Korea, by (name redacted) and Mary Beth
Nikitin.
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The DPRK statement included a reference to a “discussion of issues concerning the lifting of
sanctions on the DPRK and provision of light water reactors” as priorities once the Six-Party
Talks have resumed. The United States did not include those issues in its statement, and they are
likely areas of continued disagreement between the parties. In the past, U.S. officials have not
supported the lifting of sanctions until after full denuclearization and a determination by the U.N.
Security Council, and have supported only “discussion” of light-water reactors in the 2005 SixParty statement.
The February 29 announcement was the culmination of several rounds of bilateral talks since
summer 2011. After the death of Kim Jong Il in December 2011, U.S. officials were uncertain
whether the new leader of North Korea, Kim Jong-Un, would agree to terms that were being
discussed. Several questions were still to be resolved even before the agreement’s collapse—
including to what extent North Koreans would grant the IAEA inspectors access to the Yongbyon
facilities, and whether the North Koreans would have agreed to U.S. requirements for monitoring
of food aid.
Additional questions surrounded the potential impact missile and nuclear testing moratoria would
have had on North Korea’s weapons programs. Some prominent analysts of North Korea’s
nuclear and missile programs emphasize that halting progress on North Korea’s ability to develop
a warhead on a long-range missile should be the United States’ top priority, and further missile
and nuclear testing would be necessary for North Korea to accomplish this.149 Others point out
that weaponization activities and a clandestine uranium enrichment facility or facilities could
continue even if a moratorium of testing and activities at Yongbyon was in place.
Proliferation Issues150
Concerns persist that North Korea will continue its proliferation of missile and nuclear
technology for a variety of motivations, including financial profit, joint exchange of data to
develop its own systems, and as part of the general provocative trend. According to DNI Admiral
Dennis Blair’s testimony to Congress in 2009, North Korea is known to have sold in the past
ballistic missiles and associated materials to “several Middle Eastern countries, including Iran,
and, in our assessment, assisted Syria with the construction of a nuclear reactor.”151 On the
likelihood of nuclear proliferation from the DPRK, the DNI assessed that
Pyongyang is less likely to risk selling nuclear weapons or weapons-quantities of fissile
material than nuclear technology or less sensitive equipment to other countries or non-state
actors, in part because it needs its limited fissile material for its own deterrent. Pyongyang
probably also perceives that it would risk a regime-ending military confrontation with the
United States if the nuclear material was used by another country or group in a nuclear strike
or terrorist attacks and the United States could trace the material back to North Korea. It is
possible, however, that the North might find a nuclear weapons or fissile material transfer
149
Siegfried S. Hecker, Robert Carlin, “North Korea in 2011: Countdown to Kim il-Sung’s Centenary,” Bulletin of the
Atomic Scientists, Vol. 68 (50), 2012.
150
Also see “Nuclear Collaboration with Iran and Syria” in CRS Report RL33590, North Korea’s Nuclear Weapons
Development and Diplomacy, by (name redacted), and “Clandestine Nuclear Program and the IAEA Investigation” in
CRS Report RL33487, Armed Conflict in Syria: U.S. and International Response, by (name redacted) and (name redact
ed).
151
http://intelligence.senate.gov/090212/blair.pdf.
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more appealing if its own stockpile grows larger and/or it faces an extreme economic crisis
where the potentially huge revenue from such a sale could help the country survive.
Due to concerns of proliferation and North Korea’s past track record, the Security Council
deliberations on a resolution condemning the May 2009 North Korean test focused on ways to
interdict North Korean shipments of missile and WMD-related technologies and prevent their
financing. U.N. Security Council Resolution 1874 calls on all states to “inspect, in accordance
with their national legal authorities and consistent with international law, all cargo to and from the
DPRK, in their territory, including seaports and airports,” if that state has information that the
cargo is prohibited by U.N. Security Council Resolutions. This would include cargo related to
heavy arms (see UNSCR 1718 (8)(a)) and nuclear-related, ballistic missile-related, or other
WMD-related programs. The resolution also calls on states to inspect suspect vessels on the high
seas, with the consent of the flag state, and prohibits “bunkering services” for such shipments
such as refueling or servicing. This is significant because North Korea reportedly ships most
goods under its own flag, and typically uses small vessels that would need refueling. Reportedly
due to objections by Russia and China, the resolution does not authorize the use of force if a
North Korean vessel resists inspection.152 The resolution also has strict provisions regarding
financial services and transfer of funds through third parties, measures that may also help prevent
proliferation-related transfers. Resolution 1874 bans all arms transfers from North Korea, and all
arms transfers to North Korea except for small arms and light weapons (which require
notification).
In addition, the Proliferation Security Initiative is a U.S.-led coordinating mechanism that is
meant to guide international cooperation in carrying out interdictions of proscribed WMD and
missile-related goods, including to or from North Korea.153 China does not participate in PSI.
Therefore, a key question for implementation of the Security Council resolution will be China’s
commitment to actual interdiction measures and willingness of others to share sensitive
information, particularly if Chinese firms are implicated, as has been the case in the past. Also,
there is little emphasis on airspace interdictions, which would be relevant, for example, in the
case of North Korean shipments passing over Chinese airspace on their way to the Middle East.
However, questions remain about the true commitment of China and others to preventing WMD
and missile-related transfers to and from North Korea, in particular because North Korea has
stated it views any interdiction as an “act of war.”
Issues for Congress
Funding154
Congress will have a clear role in considering U.S. funding for any future dismantlement of North
Korea’s nuclear facilities, as well as other inducements for cooperation as agreed in the Six-Party
Talks. U.S. assistance to nuclear disablement activities at Yongbyon was funded through the State
Department’s Nonproliferation and Disarmament Fund (NDF). The State Department paid the
152
Blaine Harden, “North Korea Says It Will Start Enriching Uranium,” Washington Post, June 14, 2009.
For background on PSI, see CRS Report RL34327, Proliferation Security Initiative (PSI), by Mary Beth Nikitin.
154
For a detailed discussion, see CRS Report R40095, Foreign Assistance to North Korea, by (name redacted) and
Mary Beth Nikitin.
153
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North Korean government for the labor costs of disablement activities, and also paying for related
equipment and fuel. Approximately $20 million was approved for this purpose. NDF funds may
be used “notwithstanding any other provision of law” and therefore may be used to pay North
Korea. DOE’s National Nuclear Security Administration (NNSA) has been contributing its
personnel as technical advisors to the U.S. Six-Party delegation and as technical teams on the
ground at Yongbyon overseeing disablement measures. NNSA has estimated it spent
approximately $15 million in support of Phase Two (Yongbyon disablement) implementation.155
Congress has also provided funding for energy assistance to North Korea under the Six-Party
Talks through the State Department’s Economic Support Fund.
Authority
Congress also plays a role in establishing legal authority for assistance to nuclear disablement and
dismantlement in North Korea. Section 102 (b) (the “Glenn Amendment” U.S.C. 2799aa-1) of the
Arms Export Control Act prohibits assistance to a non-nuclear weapon state under the NPT that
has detonated a nuclear explosive device. Due to this restriction, DOE funds cannot be spent in
North Korea without a waiver. Congress passed language in the FY2008 Supplemental
Appropriations Act (P.L. 110-252) that would allow the President to waive the Glenn Amendment
restrictions and that stipulates that funds may only be used for the purpose of eliminating North
Korea’s WMD and missile-related programs.156 If the President had exercised the Glenn
Amendment waiver authority, then DOE “will be able to procure, ship to North Korea, and use
equipment required to support the full range of disablement, dismantlement, verification, and
material packaging and removal activities that Phase Three will likely entail.”157 NNSA estimated
that this would cost over $360 million in FY2009 if verification proceeded and North Korea
agreed to the packaging and disposition of separated plutonium and spent fuel at Yongbyon.
Because North Korea conducted an underground nuclear test on May 25, 2009, the waiver may
no longer be issued under P.L. 110-252. The law stipulated that a nuclear test after the date of
enactment would nullify the waiver authority.158
Congress had expressed concern that the Department of Energy have enough funds available to
support the disablement of North Korea’s nuclear weapons arsenal and production capability. In
the FY2008 Consolidated Appropriations Act, the Committees on Appropriations provided DOE’s
NNSA with funding discretion to provide up to $10 million towards its activities in North Korea.
It also directs the department to submit a supplemental budget request if additional resources are
required during FY2008.159 However, due to North Korean withdrawal from the Six-Party Talks,
Congress did not fund Administration requests in the FY2009 Supplemental Appropriations or the
155
Statement of William H. Tobey, National Nuclear Security Administration, U.S. Department of Energy, to the
Senate Committee on Armed Services, July 31, 2008.
156
Similar language appeared in the Senate version of the FY2009 Duncan Hunter National Defense Authorization Act
(P.L. 110-417), but was not included in the House version. The final act includes it under “legislative provisions not
adopted” under Title XII, since the waiver authority was passed earlier in the FY2008 Supplemental. See joint
explanatory note: http://armedservices.house.gov/pdfs/fy09ndaa/FY09conf/
FY2009NDAAJointExplanatoryStatement.pdf.
157
Tobey testimony, ibid.
158
In P.L. 110-252 Section 1405 (b)(3), there is an exception for activities described in Subparas A or B of
section102(b)1 of AECA. This includes “transfers to a non-nuclear weapon state a nuclear explosive device,” and “is a
non-nuclear-weapon state and either (i) receives a nuclear explosive device, or (ii) detonates a nuclear explosive
device.”
159
See p. 50 of http://www.rules.house.gov/110/text/omni/jes/jesdivc.pdf.
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FY2010 Consolidated Appropriations Act. The State Department’s NDF, which did receive
funding, could be used for denuclearization assistance in the case of a breakthrough in the talks.
Beyond the Glenn amendment restrictions, Department of Defense funds must be specifically
appropriated for use in North Korea. Section 8045 of the FY2008 Defense Appropriations Act
says that “None of the funds appropriated or otherwise made available in this Act may be
obligated or expended for assistance to the Democratic People’s Republic of Korea unless
specifically appropriated for that purpose.” Section 8044 of the FY2009 Consolidated Security,
Disaster Assistance, and Continuing Appropriations Act, 2009 (P.L. 110-329) also contains this
language. However, authorization was given for CTR funds to be used globally. The FY2008
Defense Authorization Act specifically encourages “activities relating to the denuclearization of
the Democratic People’s Republic of Korea” as a potential new initiative for CTR work. Senator
Richard Lugar has proposed that the CTR program be granted “notwithstanding authority”160 for
this work since the Defense Department’s experience in the former Soviet Union, expertise and
resources could make it well-positioned to conduct threat reduction work in North Korea and
elsewhere. The Department of Defense did not work on recent disablement efforts, but there may
be a future role for DOD if North Korea in the future agrees to dismantlement work.
Policy Guidance
Congress may choose to influence the course of negotiations with North Korea through
legislation that limits or places requirements on U.S. diplomatic actions. For example, the North
Korean Counter-Terrorism and Non-Proliferation Act (H.R. 3650) introduced in the 110th
Congress called for certification by the President that North Korea has met a range of
nonproliferation and political benchmarks before the Administration could lift any U.S.
sanctions.161 Congress could establish reporting requirements on progress, or condition
appropriations or disbursement to North Korea upon verification measures.162 Congress could
also be involved in other aspects of potential changes in U.S. relations with Pyongyang, such as
the monitoring of human rights issues, funding for further denuclearization steps including
verification provisions, and establishment of normalized ties once nuclear dismantlement has
been achieved. Congress also plays a role in setting sanctions policies, as in the bill Security
through Termination of Proliferation Act of 2009 (H.R. 485).
Congress also sometimes gives its sense of what actions North Korea should take. House
Resolution 1735, passed by the House on December 1, 2010, called on North Korea to
immediately cease any and all uranium enrichment activities and take concrete steps to
dismantle, under international verification and assistance, all sensitive nuclear facilities, in
accordance with United Nations Security Council Resolutions 1695 (2006), 1718 (2006), and
1874 (2009);
This resolution was passed following North Korea’s unveiling of a uranium enrichment plant at
Yongbyon in November 2010 and its attack on Yeonpyeong Island.
160
So that funds may be used “notwithstanding any other provision of law.” Senator Richard Lugar, Remarks to
National Defense University, October 2, 2008. http://lugar.senate.gov/record.cfm?id=304026&&.
161
This bill was introduced and referred to the House Committee on Foreign Affairs. H.R. 3650, September 25, 2007.
162
For example, see S.Res. 399.
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Congress may also wish to examine the implementations of multilateral sanctions on North
Korea. The United Nations Security Council (UNSC) has passed resolutions condemning North
Korean missile and nuclear tests and imposing increasingly strict sanctions on the alreadyisolated regime. The resolutions have condemned the tests, and called for North Korea to abandon
its ballistic missile and nuclear programs. UNSC sanctions on North Korea primarily ban all trade
in military goods and WMD-related and missile technologies, as well as forms of financial
support that could contribute to prohibited DPRK weapons programs. However, the UNSC
sanctions are not an embargo, and explicit exclusions are made for humanitarian and
denuclearization aid. Several problems arise in implementation especially related to Chinese
companies’ trade in dual-use goods to North Korea. A UN sanctions committee and Panel of
Experts monitor implementation of international sanctions on North Korea.
Author Contact Information
Mary Beth Nikitin
Specialist in Nonproliferation
[redacted]@crs.loc.gov, 7-....
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