The deal - so secret that the British wanted 'nothing to be put in writing' - suggests a degree of duplicity by Harold Macmillan, the Prime Minister at the time, who said in his 1973 memoirs that he had repeatedly urged President Kennedy to resist the military option during the crisis.
With the Public Record Office at Kew, west London, preparing for the annual release of 30-year British government papers on 1 January, details of the Anglo-American agreement highlight Whitehall's secrecy.
Maurice Frankel, the campaign's director, said last night that the United States had released about 15,000 pages of declassified records on the Cuban missile crisis since 1976.
'The US Freedom of Information Act is still a major source of information about British history - even about our safety,' he said. 'We still have to rely on the openness of other governments to reveal what our own government keeps secret.'
The papers show that weeks after the bungled landing by Cuban exiles at the Bay of Pigs in April 1961 - and more than a year before Soviet missiles were detected in Cuba - the US State Department asked David Bruce, ambassador to London, to seek British permission to use a base on Mayaguana Island, in the British Bahamas, to mount air-strikes against Cuba. In a cable dated 13 May 1961, Mr Bruce was told to find out whether Whitehall would seek a 'quid pro quo, and if so, what?'
The State Department told him: 'It is our intent to use Mayaguana airfield only if no other means are available to support required number of tactical aircraft involved. We foresee there may not be sufficient aircraft carriers in (the) area to fulfil this mission. Facilities in US too distant. We recognise use of the Mayaguana airfield would require consent of HMG and that seeking (to) obtain this consent could pose political considerations (of a) most serious nature. However, unless in your view these political considerations militate against approaching HMG at this time, it is requested that appropriate steps be taken to obtain its consent . . . In this regard, you may assure (the) British no action would be taken, in terms of pre-stocking supplies or other activities which would in any way suggest contemplated tactical use of facility, until its use becomes necessary.'
British agreement to the plan was revealed in a US Marine Corps memorandum of October 1962, when the United States discovered Soviet nuclear missiles on Cuba. It said: 'The British government has agreed the US may proceed with the prepositioning of supplies and equipment at Mayaguana, Bahama Islands. Conditions of the Agreement include the following: (1) Nothing is to be put in writing; (2) Facilities are not to be put to active use without prior agreement of British government.'
In the event, following a US naval blockade of Cuba, and the real fear of nuclear war, the Soviet Union backed down and withdrew the missiles. Mark Fisher, the Labour MP whose Right to Know Bill is due for its Second Reading in the Commons on 19 February, said yesterday: 'It's time we had the right to know what our government is doing in our name. Ministers should not be free to publicise the information which helps them, and suppress the rest.'
But under the terms of Mr Fisher's Private Member's Bill, information could be withheld if disclosure would cause significant damage to defence, security, foreign relations, law enforcement, privacy, and other interests - which would ensure secrecy for secret international defence agreements.