345. National Security Decision Memorandum 1241


  • The Secretary of State
  • The Secretary of Defense
  • The Chairman, Joint Chiefs of Staff


  • US–UK Nuclear Relations

The President has reviewed the NSSM 123 Study2 and approves US assistance to the UK Super Antelope missile improvement program. Approval is subject to the qualifications indicated in this memorandum.

Our assistance through the Project Definition phase does not commit the US, necessarily, to continued assistance, should the UK decide to produce and deploy this improved system. That issue will be reviewed and decided by the President at a later date. However, if the British should request assistance related to the Post Project Definition program before the end of the Project Definition phase, we will review such requests on a case by case basis. Moreover, the UK should understand that we will wish to reserve the right to review, on a case by case basis, some of the highly visible aspects of our assistance (e.g., presence of UK personnel at US underground nuclear tests or use of US missile test ranges). Our willingness to cooperate in the Project Definition study cannot imply an assurance regarding the successful outcome of the project, in view of the limited US experience in some of the areas to be studied.

The Departments of State and Defense should, through appropriate channels, inform the UK of our decision and the considerations in the preceding paragraph. [2½ lines not declassified]

The NSC Senior Review Group shall assume responsibility for implementing and coordinating our assistance to the UK on the Super Antelope project. All interested agencies will be involved as appropriate, and periodic status reports will be forwarded to the President. Decisions on particularly sensitive aspects of cooperation that might become publicized, or which may have broader international implica[Page 1021]tions, will be referred to the SRG by the agencies involved, and, when necessary, referred to the President. Decisions on any requests for support related to the Post Project Definition program will be referred by the SRG to the President.

This cooperation with the UK is highly sensitive and should be treated by all agencies on a highly classified basis. The UK should be informed of the sensitive nature of our cooperation.

The Atomic Energy Commission is authorized to allocate space to the UK at US underground nuclear effects tests as appropriate to meet the objectives of the Super Antelope project. The presence of UK personnel planned for the next test is approved, but the presence of UK personnel at future tests will be referred to the SRG for decisions.

The Atomic Energy Commission, in coordination with the Departments of State and Defense, will inform the Joint Committee on Atomic Energy of our proposed cooperation with the UK on this project.

Henry A Kissinger
  1. Source: National Archives, Nixon Presidential Materials, NSC Files, Box 364, Subject Files, National Security Decision Memoranda (NSDM’s) Nos. 97–. Top Secret; Sensitive. Copies were sent to the Director of Central Intelligence, the Chairman, Atomic Energy Commission, and the Director, Arms Control and Disarmament Agency.
  2. Document 344.