<p>I have been asked to reply on behalf of the Ministry of Defence.</p><p>This was addressed in a Ministry of Defence April 2000 report on historical accounting and plutonium, a summary of which is available in the National Archives at the following link:</p><p>http://webarchive.nationalarchives.gov.uk/20060130214247/http://www.mod.uk/publications/nuclear_weapons/accounting.htm</p><p>Plutonium for nuclear weapons was produced in the UK defence reactors at the Windscale Piles, Calder hall and Chapelcross. The UK Government announced a moratorium on the production of nuclear materials for explosive purposes in 1995.</p><p>Since the 1998 Strategic Defence Review, all reprocessing in the UK has been conducted under the Euratom/International Atomic Energy Agency Safeguards agreement. There have been some withdrawals of plutonium from safeguards, for analysis, temporary handling or processing when such services were not available in the civilian sector. It is not possible to determine where this plutonium was created. These withdrawals are of a type and quantity not suitable for weapons use; information can be found on the Office of Nuclear Regulation website at the following link:</p><p>http://www.hse.gov.uk/nuclear/safeguards/withdrawals.htm</p>