The British team completed the development of the agreement in March 1963 and copies were put into discussion.  Work contracts were announced this month. The Polaris boats were the largest submarines built until then in the United Kingdom and were built by the Armstrong Shipbuilders from Vicker to Barrow-in-Furness and Cammell Laird to Birkenhead. For reasons similar to those of the US Navy, the Royal Navy decided to deploy the ships to Faslane, on gareloch, near the US Navy base, on the St. Loch.  The downside of the terrain was that it insulated the Polaris vessels from the rest of the navy.  The Polaris Purchase Agreement was signed on April 6, 1963 in Washington, D.C. by Ormsby-Gore and Dean Rusk, U.S. Minister of Foreign Affairs.  The Polaris purchase agreement provided a strong framework for missile negotiations and return systems.  The legal agreement took the form of an amendment to polaris` purchase contract through an exchange of notes between the two governments, so that “Polaris” now included in the original the purchase of Trident. Some changes have also been made to the classified annexes of the Polaris sales contract to eliminate the exclusion of penetrating aid.  Under the Polaris sales agreement, the United Kingdom paid a 5% tax on the costs of the equipment delivered, recognizing the research and development costs already incurred in the United States.
For Trident, a payment of $116 million has been replaced.  The United Kingdom purchased the Trident system from the United States and set it up on its own submarines, which had only 16 rocket tubes as Polaris and not the 24 in the American class of Ohio. The first Vanguard-class submarine, HMS Vanguard, was commissioned in December 1994, at the end of the Cold War.  A U.S. mission visited the United Kingdom. It was led by Paul H. Nitze, Deputy Minister of Defence for International Security Issues, which included Walt W. Rostov, Director of Political Planning at the Ministry of Foreign Affairs, and Admiral Ignatius J.