HC Deb 13 May 1986 vol 97 cc541-3
4. Mr. Tony Lloyd

asked the Secretary of State for Defence what need there is for nuclear testing by or on behalf of the United Kingdom.

Mr. Younger

The United Kingdom requires to carry out nuclear tests in order to maintain the effectiveness of its nuclear defence capabilities.

Mr. Lloyd

Given the evidence from the Chernobyl disaster and the effects of radiation, even at low radiation yields equivalent to a 1 kilotonne bomb, can the Secretary of State tell us whether Britain's interests would be better served by guaranteeing that our missiles are sent on a day when the wind is in the right direction, or by moving towards a verifiable test ban treaty, which we now know is possible?

Mr. Younger

The Government's policy is to work in every way possible for a comprehensive test ban treaty. The principal obstacle to a treaty being concluded now is the absence of any effective verification procedures. I do not think that there is any connection with the Chernobyl disaster other than that.

Mr. Bill Walker

Does my right hon. Friend agree that nuclear warheads come in a wide range of sizes, with the ability to cause equally wide-ranging devastation, and that they can also be fitted to a variety of different delivery systems? Does he further agree that, to bring together the right warheads with the right delivery systems to meet the changing needs of our defence requirements, it is essential that continuing testing goes on while the opposite side are doing the same?

Mr. Younger

We all wish that a way can be found, as soon as possible, of eliminating nuclear weapons altogether, but, while they are there, testing is essential for safety and operational reasons. The Government's policy is to do everything possible to negotiate a comprehensive test ban treaty as soon as verification can be made credible.

Mr. Strang

Is not the Government's assertion that verification procedures and techniques are not yet available rejected by leading scientists, not only in the Soviet Union and the United States, but here? Does not his answer to my hon. Friend the Member for Stretford (Mr. Lloyd) make it clear that, far from wanting a comprehensive test ban treaty, the Government simply pay lip-service to that objective, while their real objective is to continue nuclear testing to develop new nuclear weapons?

Mr. Younger

I do not accept any of that. One can find scientists in this country who will say that verification can be achieved, and others who say the opposite. The advice that is given to me is that verification is very far from being 100 per cent. effective, or even acceptable in its present state. We must do all that we can to encourage the Soviet Union to agree further measures on verification, so that we can make progress.

Mr. Alexander

Is it not the case that while Polaris and Trident are American delivery vessels, the warheads are British and, if they are to work, they must be tested?

Mr. Younger

My hon. Friend is right. While these weapons exist and we have them, for all these reasons we must test them from time to time. However, none of that is against our ultimate aim of having a comprehensive test ban treaty.

Mr. Wallace

Is not the Secretary of State's last answer the key to it—that verification is put up only as a thin excuse, which is not even accepted in many parts of the United States Government, for not progressing towards a comprehensive test ban treaty? Is not the development of the Trident warhead stopping Britain from taking advantage of its unique position to take initiatives in seeking a comprehensive test ban treaty?

Mr. Younger

If the hon. Gentleman thinks a little further about this matter, he will appreciate that a comprehensive test ban treaty, or any test ban treaty, which it was not possible to be absolutely certain that we could verify, would be worth nothing and would be an extremely dangerous measure for us to embark upon.

Mr. Shersby

Further to the question by the hon. Member for Stretford (Mr. Lloyd), can my right hon. Friend say whether it is the policy of Her Majesty's Government to carry out atmospheric tests with nuclear weapons?

Mr. Younger

There is no change in our normal policy on nuclear tests, and we do not make advance announcements of when and where they will take place.

Mr. Denzil Davies

The right hon. Gentleman's first answer was the correct one. He made it clear that the Government will not agree to a comprehensive ban treaty because that would deny the effectiveness that the Government require. Why does he not come clean and make it clear that it is nothing to do with verification or safety, but that, to get Trident, the Government must test the warheads?

Mr. Younger

The right hon. Gentleman is wrong. It is clear that a test ban treaty, or a test ban, without credible means of verification is not worth anything, and it would be an extremely dangerous course on which to embark. I hope that, whatever other disagreements we may have on this difficult subject, we can at least agree that if we are to have a test ban, we must have adequate verification first.