This weakness came to the fore most prominently in 1981 with the Reagan administration's decision to sell AWACs spy planes to the Saudis.

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Developed by Northrop Grumman, it is designed to conduct high altitude surveillance missions and replace the U-2 spy planes, in use since the 1950s.

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Army sources in Colombia say this will support an American-built intelligence centre, primed to supply the Colombians with information from satellites and spy planes, at Tres Esquinas in the south.

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Oh, and super secret Army intelligence spy planes.

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The strategic defence review included plans to scrap Harrier jump jets, the Navy's flagship HMS Ark Royal and Nimrod spy planes, as well as 42, 000 Ministry of Defence and armed forces jobs.

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It also underscores a little-remembered fact: Even in an era of high-tech drones, the Air Force still relies on manned spy planes such as modern versions of the U-2, five decades after the famous exchange.

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Into that gap fly spy planes.

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Mr French said one of the "Spy in the Sky" planes had been completed.

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Clayton Laurie, a historian at the Center for the Study of Intelligence at the CIA, said the spy agency needed highly skilled military pilots to fly the planes over the Soviet Union.

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