Statement by Deputy Press Secretary Speakes on the Sale of the Trident II Missile System to the United Kingdom
Today in London, the British Government is informing the House of Commons of its decision to purchase from the United States the Trident II (D-5) missile system, rather than the Trident I (C-4) system. When the President decided in October 1981 that the U.S. Navy would develop the Trident II missile, he informed the British Government that it would be available for purchase by the United Kingdom. In an exchange of letters today, Prime Minister Thatcher formally requested that the United States sell the Trident II missile, and the President agreed.
Beginning during the Second World War, the United States has cooperated intimately with the United Kingdom on nuclear matters. In President Roosevelt's administration, American and British scientists began working together on the development of nuclear weapons. In 1962 at Nassau, President Kennedy agreed to assist the British in the development of their strategic nuclear forces by selling Polaris missiles to the United Kingdom. Today's announcement signals a continuation of this long-standing cooperation, which is a central element in the close cooperation between the United States and the United Kingdom.
The primary reason for the British choice of the Trident II missile over the Trident I is to maintain commonality with the United States Navy. Although the performance of the Trident I was adequate for British purposes, there would be a long-term logistic and cost penalty associated with the uniqueness of the system once the United States Navy made the transition to the Trident II missile.
The administration believes the independent British strategic nuclear force which is assigned to NATO makes an important contribution to the ability of the North Atlantic Alliance to deter Soviet aggression. For this reason, the President has decided to continue to assist the United Kingdom in the maintenance of a modernized, independent British deterrent force into the twenty-first century. In addition, the President's letter welcomes the Prime Minister's commitment to use savings from cooperation in the strategic nuclear field to strengthen British conventional forces, which are also vital to the NATO deterrent.
Ronald Reagan, Statement by Deputy Press Secretary Speakes on the Sale of the Trident II Missile System to the United Kingdom Online by Gerhard Peters and John T. Woolley, The American Presidency Project https://www.presidency.ucsb.edu/node/245599