J. Edgar Hoover sensationally suggested that Prince Philip may have been “involved” with the two women at the heart of the Profumo sex scandal. Hoover, the then-head of the FBI, sent a cable to the US embassy in London claiming he had been told that the prince had links to both Christine Keeler and Mandy Rice-Davies .

The cable, which was sent more than 60 years ago and has since been languishing in US Department of Justice archives, has been made available after a long-running Freedom of Information request. It contains a claim made by Thomas Corbally, an American businessman working in the industrial espionage sector, who was friends with Stephen Ward , the fixer at the heart of the scandal..