Portal:Nuclear technology/Articles/53
In 1952, the United Kingdom became the third country (after the United States and the Soviet Union) to develop and test nuclear weapons, and is one of the five nuclear-weapon states under the Treaty on the Non-Proliferation of Nuclear Weapons. As of 2025[update], the UK possesses a stockpile of approximately 225 warheads, with 120 deployed on its only delivery system, the Trident programme's submarine-launched ballistic missiles. Additionally, United States nuclear weapons have been stored at RAF Lakenheath since 2025.
The UK initiated the world's first nuclear weapons programme, codenamed Tube Alloys, in 1941 during the Second World War. At the Quebec Conference in August 1943, it was merged with the American Manhattan Project. The British government considered nuclear weapons to be a joint discovery, but the American Atomic Energy Act of 1946 (McMahon Act) restricted other countries, including the UK, from access to information about nuclear weapons. Fearing the loss of Britain's great power status, the UK resumed its own project, now codenamed High Explosive Research. On 3 October 1952, it detonated an atomic bomb in the Monte Bello Islands in Australia in Operation Hurricane. In total the UK conducted 45 nuclear tests, 12 in Australia, 9 in the Pacific, and 24 at the Nevada Test Site, with its last in 1991.
The British hydrogen bomb programme's success with its Operation Grapple Pacific nuclear testing led to the 1958 US–UK Mutual Defence Agreement. This nuclear Special Relationship between the two countries has involved the exchange of classified scientific data, warhead designs, and fissile materials such as highly enriched uranium and plutonium. UK warheads are designed and manufactured by the Atomic Weapons Establishment.
The Royal Air Force's V bomber fleet was responsible for the UK's independent strategic nuclear weapons between 1954 and 1969. Other RAF aircraft continued to be used in a tactical nuclear role until the 1998 decommissioning of their WE.177 bombs. The RAF planned to operate the Blue Streak intermediate-range ballistic missile (IRBM), but cancelled it in 1960.
The RAF also operated Thor IRBMs under US custody between 1959 and 1963. Under Project E, the US also supplied the RAF and British Army of the Rhine with US-custody tactical bombs, missiles, depth charges andartillery from 1957 to 1992. US Air Force nuclear weapons were stationed in the UK between 1954 and 2008, and from 2025. In 2025, the UK announced plans to procure 12 F-35A aircraft capable of delivering US tactical bombs. These would form a part of NATO's dual capable aircraft programme and will be based at RAF Marham.
Since 1969, the UK has operated the continuous at-sea deterrent, providing ballistic missile submarine patrols with the strategic strike role. Under the 1962 Nassau Agreement and 1963 Polaris Sales Agreement, the US supplied the UK with Polaris missiles and nuclear submarine technology, in exchange for the general commitment of these forces to NATO. In 1982, the Polaris Sales Agreement was amended to allow the UK to purchase Trident II missiles. Since 1998, the Trident has been the only operational nuclear weapons system in British service. The delivery system consists of four Vanguard-class submarines based at HMNB Clyde in Scotland. Each submarine is armed with up to sixteen Trident II missiles, each carrying warheads in up to eight multiple independently targetable re-entry vehicles (MIRVs). With at least one submarine always on patrol, the Vanguards perform a strategic deterrence role. (Full article...)