TOP SECRET SENSITIVE No Objection To Declassification 2008 06 11 N LC-132-111-2-1-8 MEMORANDUM _ NATIONAL SECURITY COUNCIL March 14 1980 MEMORANDUM FOR • DAVE GOMPERT WALT SLOCOMBE SUBJECT US I UK Nuclear Cooperation TS Attached for your background are 1 the UK's suggested Prime-Minister-to President letter with our suggested alterations and 2 the proposed Presidential reply The reply has been changed slightly since you saw it last Note that in both letters I have put in squiggly brackets f material related to SNM Unless the re is a change in the murky SNM situation we may want to delete this material Jim Thomson TOP SECRET SE lSITIVE Review 3-14-2010 No Objection To Declassification 2008 06 11 NLC-132-111-2-1-8 TOP SE6RET n No Objection To Declassification 2008 06 11 N LC-132-111-2-1-8 j S r o' v '- lo o v 11 I • - J D AET LETTER ffiOM PRIME MI STER TO PRESIDENT As you wi 11 lmow from re cent exchanges between us the United Kingdom Gover p ment attaches great importance to the maintenance of a nuclear eterrent capability It will be necessary to replace the present Pblari s force in the early 1990s and having reviewed the options the Goveniment has concluded that the L'l'rident weapon system best meets the need to maintain a viable deterrent capability into the 21st century I write therefore to ask you whether the United States Government would be prepared in continuation of the cooperation which has existed between our Governments n this field since the Polaris Sal es Agreement of the 6th of April 1963 to supply on a continuing basis tr°rident jJ missiles equipment and supporting services 11 seaman si ai Jr0 p •e tluat iJ r eh i1 1 •• a ee l ftl' PPJ i § d whether the Uni tadStates Goveria ment would be willing to a mend further the Agreement for Cooperation on the Uses of Atomic Energy for Mutual Defence Purposes of the 3rd of Jul y 1958 in respect of the supply of special nuclear materials for the United Kingdom deterrent programm y The United Kingdom Government would wish to purchase sufficient missiles collll lete with multiple independently targettable re-entry vehicles and less only the warheads themselves together with equipment and supporting services on a continuing basis to introduce and maintain a force of British submarines close coordination being maintained between the Executive Agencies of the two Gove rnments in order to assure compatibility of equipment and would also wish to procure such special nuclear materials as were needed i and were beyond their own capacity to provide to enable them to produce the warheads The su cessor to the Polaris force will be assigned to NATO like Polari and except where the Uni tad Kingdom Goven unent may decide that supreme national interests are at stake the successor force will be used for the pu oses of international defence of he Western Alliance in all circumstances It is my i mderstanding No Objection To Declassification 2008 06 11 NLC-132-111-2-1-8 •v• _ _ _ _ ' ' - - - N o Objection To Declassification 2008 06 11 NLC-132-111-2-1-8- 0 - 2 - TOP SECRET understanding that cooperation in the modernisation of the United Kingdom nuclear deterrent in tbis way would be consistent with the present a nd prospective international obligations of both parties In particular I should like to assure you that the United Kingdom contlnues to give whole-hearted support to the NATO LongTerm Defence Programme with its emphasis on the strengthening of conventional forces ' e United Kingdom Govenunant has substantially increased its defence spending in accordance with NATO's collective policy and l lans to make further such increases in the future in order to improve the effectiveness cf' its all-round contribution to Alliance deterrence and defence 1 • - fl r _ ·- -·Ill-' I''• - If the Pnited States Government is prepared to meet this request I hope that as the next step the United States Government will be prep1a red to receive technical and financial missions to pursue these matters using the framework of the Polaris Sales Agreement where appropriate • r -- M _Jw L 'Ml ' ' w- A Cl J 0- J f l • ' - - j__ l Q t GoWv v __ • _ • - J $-• - -n- _ - At- - if-•-¥ 2 W - _ _ _ _ _ _ _ _ ' ' '£ r J- • •- ·-1 •· __ •'lfll'illff-' -e-' • I · _ - '4' - _ - lf i t ii •· No Objection To Declassification 2008 06 11 NLC-132-111-2-1-8 l --- -•- L - TOP SECRET No Objection To Declassification 2008 06 11 N LC-132-111-2-1-8 ti t J •• DRAFT LETTER FROM THE PRESIDENT TO THE PRIME MINISTER Dear Madame Prim Minister In reply to your letter of 1 am pleased to confirm that the United $tates attaches significant importance to the nuclear deterrent capability of the United Kingdom and to close cooperation between our two governments in maintaining and modernizing that capability To further that objective the United States is prepared to supply the United Kingdom TRIDENT I missiles equipment and supporting services as you propose in your letter subject to and in accordance with applicable United States la and procedures rn addition the United States is willing in principle to supply special nuclear materials for the United Kingdom deterrent program which were beyond your own capacity to provide subject of cours e to the United States government's ability to provide such 1 materials in light of its requirements and availability of supply I view as important your statements that the POLARIS successor force will be assigned to NATO and that you intend to use savings created by our nuclear cooperation to upgrade the United Kingdom's conventional force As you know I regard the strengthening of NATO's conventional and nuclear forces as of highest priority for Western security I agree that as the next step in implementing the se agreements our two governments should initiate negotiations on the technical and financial terms of the sale of TRIDENT I missile system from the United States to the United Kingdom Sincerely The Right Honorable Margaret R Thatcher M P Prime Minister London No Objection To Declassification 2008 06 11 NLC-132-111-2-1-8