340. National Security Study Memorandum 1231


  • The Secretary of State
  • The Secretary of Defense
  • Director of Central Intelligence


  • US–UK Nuclear Relations

The President has directed that a study be prepared to review current issues of nuclear cooperation with Great Britain.

In particular, the study should address:

1. The extent to which we are already committed to assist the UK in improving its strategic nuclear force under existing agreements.

2. The implications of US assistance to the British in their efforts to improve the capability of their present Polaris systems through the “project definition phase.”

3. The long run implications for the US of a deeper involvement in the UK effort to develop and deploy an improved Polaris system, including an assessment of British strategic objectives and a possible future UK request for MIRV technology.

This study will be prepared by an Ad Hoc Group comprising representatives of the addressees and the NSC staff and chaired by the Chairman of the NSC Interdepartmental Political Military Group. The completed study, which will be considered by the Senior Review Group, should be forwarded to the Assistant to the President for National Security Affairs not later than May 10.2

Henry A. Kissinger
  1. Source: National Archives, Nixon Presidential Materials, NSC Files, NSC Institutional Files (H–Files), Box H–182, National Security Study Memoranda, NSSM 123. Top Secret; Sensitive. A copy was sent to the Chairman, Joint Chiefs of Staff.
  2. Document 344. The SRG did not meet to discuss the completed study.