§ Mr. Harry BarnesTo ask the Secretary of State for Defence, further to his oral replies to the hon. Member for Glasgow, Rutherglen (Mr. McAvoy) of 19 November,348W Official Report, column 136, if he will list all the relevant international treaties on nuclear testing; what are the reasons for the practice of refusing to confirm or deny that a British nuclear warhead test is to take place; how the operational safety of nuclear weapons benefits from nuclear tests conducted at the Nevada nuclear test site; and what proportion of British nuclear tests conducted at Nevada have been for the purpose of safety tests.
§ Mr. Archie HamiltonInternational treaties related directly to nuclear testing are:
- a. The Partial Test Ban Treaty;
- b. The Peaceful Nuclear Explosions Treaty;
- c. The Threshold Test Ban Treaty.
The United Kingdom is party only to the first of these. The second and third are bilateral between the United States and Soviet Union. As United Kingdom nuclear tests are carried out at the United States test site in Nevada, however, we invariably respect their provisions. In addition, nuclear testing is covered in the preamble to the nuclear non-proliferation treaty.
For reasons of safety and national security it has been the practice of successive Governments not to make a prior announcement of forthcoming United Kingdom nuclear tests. The development of new safety features is an important element of the United Kingdom nuclear test programme, but I am not prepared to give further details.