Cold War spy pact details revealed
Details of the top secret Cold War spying pact between Britain and the United States have been made public for the first time.
The 1946 UKUSA Agreement set out sweeping arrangements for sharing almost all communications intelligence on foreign powers gathered by the two countries.
It took 60 years for the UK's Cheltenham-based Government Communications Headquarters (GCHQ) to confirm that the deal even existed. Now the text of the ground-breaking seven-page agreement has been made available online by the National Archives in Kew, west London.
Headed "top secret", the document sets out the terms for Britain and the US exchanging virtually all intelligence relating to intercepted communications of foreign governments and militaries.
The pact stressed that the exchange of intelligence would be unrestricted, except when both sides agreed that specific information could be excluded. "It is the intention of each party to limit such exceptions to the absolute minimum and to exercise no restrictions other than those reported and mutually agreed upon," it said.
Emphasising the utmost secrecy of the deal, another clause stated: "It will be contrary to this agreement to reveal its existence to any third party whatever."
The document was signed on March 5, 1946, by Colonel Patrick Marr-Johnson on behalf of the UK's London Signals Intelligence Board and Lieutenant General Hoyt Vandenberg for the US State-Army-Navy Communication Intelligence Board.
The UKUSA Agreement, which is unique in the Western intelligence world, formed the basis for co-operation between the two countries throughout the Cold War and into the modern day. It was expanded to include Canada in 1948 and Australia and New Zealand in 1956.
Ed Hampshire, principal records specialist at the National Archives, said: "The agreement represented a crucial moment in the development of the 'special relationship' between the two wartime allies and captured the spirit and practice of the signals intelligence co-operation which had evolved on an ad-hoc basis during the Second World War. As the threat posed by Nazi Germany was replaced by a new one in the east, the agreement formed the basis for intelligence co-operation during the Cold War."
- The files can be viewed for free for a month at www.nationalarchives.gov.uk/ukusa