§ Q1. Mr. A. Hendersonasked the Prime Minister whether he will instruct his representatives at the Geneva Disarmament Conference to propose a test ban treaty, banning all high altitude and atmospheric tests, to be controlled by existing means of detection, together with a temporary moratorium on underground tests pending further scientific examination of the means of detecting such tests.
§ The Prime Minister (Mr. Harold Macmillan)I recognise that the right hon. and learned Gentleman, like Her Majesty's Government, is anxious to try anything which may result in an acceptable solution of these difficult problems. The difficulty about his present proposal 197 is that a temporary moratorium might turn out to be a very long moratorium and there would be no certainty that the Soviet Government were observing it.
§ Mr. HendersonIs it not time that Her Majesty's Government looked ahead to the conclusion of the present American series and the projected Soviet series of tests, and should they not propose a test ban treaty to come into operation on that date banning all high-altitude, atmospheric and underground tests, to be controlled by existing instruments, as suggested by the scientist, Professor Don Leet, and make provision for the minimum amount of verification?
§ The Prime MinisterThat is broadly the sort of proposal we have tried to get through. The difficulty still remains in the last sentence, in the right hon. Gentleman's phrase about a reasonable amount of verification.
§ Mr. GrimondWhile sympathising with the Government's difficulty in dealing with the Russians over this matter, may I ask whether the right hon. Gentleman is advised that by underground testing alone a really significant advance can be made in nuclear warfare?
§ The Prime MinisterIt has its considerable importance, and I do not think that at this stage we could contemplate a treaty that was not comprehensive.
§ Mr. MendelsonWhilst recognising the importance of the element of verification in these matters, may I ask the Prime Minister whether he has seen the new proposal made by Mr. Erlander, the Prime Minister of Sweden, in support of the proposals made by the eight neutralists, which would allow for an invitation to be sent by the Government concerned and for inspection by agreement? Would the right hon. Gentleman give the Government's support to the Swedish Prime Minister in this initiative?
§ The Prime MinisterThere are all sorts of variations of the possible way out, but so far they have all come to grief on the very point which the hon. Member mentioned.
§ Mr. HendersonCan we take it that the Prime Minister is expressing the support of Her Majesty's Government for the proposals contained in my 198 Question provided that the Soviet Union is prepared to agree to a minimum amount of verification in cases of dispute?
§ The Prime MinisterWe have first to settle and get further information about the system of instrumentation and then, even if we have that settled, there is the vital question of verification.
§ Q5. Mrs. Castleasked the Prime Minister whether his scientific advisers have now had an opportunity of studying the claims of Professor Lewis Don Leet to have discovered a scientifically incontestable method of detecting underground nuclear tests; and whether he will make a statement.
§ The Prime MinisterAs I said on 22nd May, we are always ready to look at this or any other new discovery or claim. Such evidence as is available in support of Professor Leet's claims is being studied by our scientific advisers.
§ Mrs. CastleWhen this study is complete, will the Prime Minister inform the House of Commons of its outcome? In the meantime, is the right hon. Gentleman aware that no one really knows what will be the scientific consequences of the proposed American tests of Rainbow bombs, and will he, therefore, even at this eleventh hour, plead with the United States to postpone them in order that we may see whether a test ban treaty could be negotiated in the light of this new evidence?
§ The Prime MinisterThere is certain evidence from scientists on the problem of the machines or the instrumentation necessary to discover whether an explosion is due to artificial or natural means. On that, there are, of course, a large number of experts. Sometimes these experts do not all agree. There is then the second stage, to which the right hon. learned Member for Rowley Regis and Tipton (Mr. A. Henderson) referred earlier. Even if that first stage were dealt with, as I believe it can be in time, and made more perfect, there is the question of on the spot verification.
§ Mrs. CastleWill the Prime Minister inform the House in due course whether his scientific advisers believe or do not believe that Professor Lewis Don Leet's method of verification is sound?
§ The Prime MinisterSo far, we are studying this publication in a magazine in the United States, but it is a very complicated and detailed subject and I think that our scientists must have opportunity to consider it carefully.