Updated March 2010
Introduction

The United Kingdom is a nuclear weapon state party to the Treaty on the Non-Proliferation of Nuclear Weapons (NPT), and a member of all of the major WMD nonproliferation treaties and international export control regimes. In response to its July 1998 Strategic Defence Review, the British government made substantial reductions to its nuclear forces and the 2010 Strategic Defense Review will likely precipitate further reductions.[1] Though it once possessed biological and chemical warfare programs, the United Kingdom ended both programs in the mid to late 1950s. Its limited missile program is now composed entirely of sea-launched missiles.
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Nuclear
The United Kingdom ratified the NPT in November 1968 and the Comprehensive Nuclear Test Ban Treaty (CTBT) in June 1998. The United Kingdom's current nuclear stockpile consists of fewer than 200 strategic and "sub-strategic" warheads on four Vanguard-class nuclear-powered ballistic missile submarines (SSBN). The July 1998 Strategic Defense Review precipitated major changes to the British nuclear weapons program, including the removal of air-delivered weapons from service and exclusive reliance on SSBNs for nuclear deterrence. The Review also mandated that only one submarine be on patrol at a time, it reduced the number of warheads carried to a maximum of forty-eight, and it required the missiles be de-targeted.[2] Because the first two submarines of the existing Vanguard-class fleet will be retired in 2024, in early 2007 British lawmakers accepted a plan to design a new class of replacement nuclear-armed submarines.[3] With a new Strategic Defence Review due to be conducted after the 2010 General Election, the merits of renewing Britain's Strategic Trident system will again be an issue of contention. [4] [5] Putting an end to Washington's fifty-four year nuclear presence in the United Kingdom, the United States removed its 110 B-61 gravity bombs from the Royal Air Force Base at Lakenheath in June 2008. [6]
Nuclear power provides approximately 20% of the United Kingdom's electricity, but the country's current plants are rapidly nearing the end of their lifespan. In January 2008, private energy companies received formal approval to "initiate, fund, construct, and operate" a new generation of nuclear power plants. Nuclear power is a key component of the government's strategy to meet greenhouse gas emission targets outlined under the Kyoto Protocol.[7]
The United Kingdom participates in nuclear technology export control efforts through its membership in the Nuclear Suppliers Group (NSG) and the Zangger Committee (ZAC).
Biological
Beginning in 1934, the United Kingdom weaponized anthrax and conducted research on botulinum toxin and the pathogens that cause plague and typhoid fever. [8] By the late 1950s, the United Kingdom no longer had an offensive biological weapons program, although its defensive biological program remains strong today. [9][10] London ratified the Biological and Toxin Weapons Convention (BTWC) in March 1975, and is a member of the Australia Group (AG). On 28 March 2005, the United Kingdom, the United States, and Russia issued a joint statement affirming their support for the BTWC and called on all remaining countries not party to the BTWC to implement and comply with the convention.[11]
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Chemical
The United Kingdom's World War II stockpile of chemical warfare (CW) agents included phosgene, mustard gas, and lewisite.[12] However, the country renounced its chemical weapons program in 1957 and subsequently destroyed its chemical stockpiles.[13] London ratified the Chemical Weapons Convention (CWC) in May 1996 and participates in the Australia Group (AG), an export control mechanism for chemical and biological weapons.
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Missile
The United Kingdom's nuclear deterrent resides on four Vanguard-class submarines, each outfitted to carry 16 U.S.-supplied Trident II sea-launched ballistic missiles (SLBM) and 48 warheads.[14] The U.K. shares a pool of missiles with the United States at the Strategic Weapons Facility Atlantic, Kings Bay Submarine Base, Georgia. The Royal Navy retrieves missiles from the U.S. storage area and equips warheads onboard its submarines. Although the United Kingdom has title to 58 SLBMs, it technically does not own them, and the United States handles missile servicing.[15] London terminated the nuclear role of the Tornado aircraft in 1998, bringing an end to four decades of nuclear equipped Royal Air Force aircraft.[16]
London is a member of the Missile Technology Control Regime (MTCR), whose goal is to restrict the proliferation of unmanned delivery systems capable of delivering weapons of mass destruction, and of the Hague Code of Conduct Against Ballistic Missile Proliferation (HCOC), designed to supplement and bolster the MTCR.
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Sources:
[1] Richard Norton Taylor, "Army chiefs question need for Trident nuclear deterrent," The Guardian, 23 February 2010.
[2] Joseph Cirincione, Jon B. Wolfsthal, and Miriam Rajkumar, Deadly Arsenals: Nuclear, Biological, and Chemical Threats, Second ed. (Washington, DC: Carnegie Endowment for International Peace, 2005), p. 197.
[3] Wade Boese, "UK Nuclear Submarine Plan Wins Vote," Arms Control Today 37, no. 3, April 2007, pp. 34-35.
[4] Bob Ainsworth, "Adaptability and Partnership: Issues for the Strategic Defence Review," Ministry of Defence, February 2010, p. 30. www.mod.uk.
[5] Richard Norton Taylor, "Changing the armed forces for a new kind of warfare," The Guardian, 3 February 2010.
[6] Hans M. Kristensen, "U.S. Nuclear Weapons Withdrawn from the United Kingdom," FAS Strategic Security Blog, June 2008, www.fas.org.
[7] Economist Intelligence Unit, "Economic Policy: Government approves nuclear power expansion," The Economist, 10 January 2008, www.eiu.com.
[8] Barton J. Bernstein, "Churchill's Secret Biological Weapons," Bulletin of the Atomic Scientists 43, no. 1, 1 January 1987, p. 46.
[9] Milton Leitenberg, "Biological Weapons in the Twentieth Century: A Review and Analysis," 7th International Symposium on Protection against Chemical and Biological Warfare, Stockholm, Sweden, June 2001, www.fas.org.
[10] Joseph Cirincione, Jon B. Wolfsthal, and Miriam Rajkumar, Deadly Arsenals: Nuclear, Biological, and Chemical Threats, Second ed. (Washington, DC: Carnegie Endowment for International Peace, 2005), p. 198.
[11] U.S. Department of State, "U.S., U.K., Russia Reaffirm Support for Biological Weapons Pact," U.S. Department of State International Information Programs, 28 March 2005, www.iwar.org.uk.
[12] Julian Perry Robinson, Carl-Göran Hedén and Hans von Schreeb,"The Problem of Chemical and Biological Warfare," CB Weapons Today 2, p. 127.
[13] Edward M. Spiers, Chemical and Biological Weapons: A Study of Proliferation (New York: St. Martin's Press, 1994), pp. 11, 162.
[14] Joseph Cirincione, Jon B. Wolfsthal, and Miriam Rajkumar, Deadly Arsenals: Nuclear, Biological, and Chemical Threats, Second ed. (Washington, DC: Carnegie Endowment for International Peace, 2005), p. 97.
[15] Robert S. Norris and Hans M. Kristensen, "British Nuclear Forces, 2005," Bulletin of the Atomic Scientists 61, no. 6, p. 78.
[16] Joseph Cirincione, Jon B. Wolfsthal, and Miriam Rajkumar, Deadly Arsenals: Nuclear, Biological, and Chemical Threats, Second ed. (Washington, DC: Carnegie Endowment for International Peace, 2005), p. 197.
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This material is produced independently for NTI by the James Martin Center for
Nonproliferation Studies at the Monterey Institute of International Studies and
does not necessarily reflect the opinions of and has not been independently
verified by NTI or its directors, officers, employees, agents. Copyright © 2010 by MIIS.





