Blunt was recruited by MI5 during World War II but the secret services became suspicious of him after Guy Burgess and Donald Maclean, whom he had been close friends with since their days at Cambridge University in the 1930s, defected to Russia in 1951.

The National Archives has released declassified MI5 files, including the confession of a civil servant who worked in the Cabinet Office, Treasury and Foreign Office in the 1930s, 1940s and 1950s – and spied for the Soviet Union at the same time.

Newly declassified British documents show that Queen Elizabeth II wasn’t told details of her long-time art adviser's double life as a Soviet spy because palace officials didn’t want to add to her worr

Queen Elizabeth II was not told about her long-time art adviser's double life as a Soviet spy, newly declassified documents reveal.

Queen Elizabeth II wasn’t told details of her long-time art adviser's double life as a Soviet spy because palace officials didn’t want to add to her worries, newly declassified documents reveal.

Sir Anthony Blunt, the royal family's picture surveyor and renowned art historian, finally admitted that he had been a Soviet agent since the 1930s