Anthony Blunt, who worked at Buckingham Palace as Surveyor of the Queen’s Pictures, was secretly a Soviet spy during WWII.

Queen Elizabeth II was not officially informed for almost a decade that one of her most senior courtiers had confessed to being a Soviet spy, according to newly released MI5 files.

Documents newly declassified by MI5, Britain's internal intelligence agency, show the late Queen Elizabeth II was not informed for almost 10 years that a member of her staff had spied for the then-Soviet Union.

The files about royal art historian Anthony Blunt are among a trove from the intelligence agency MI5 released Tuesday by Britain’s National Archives.

Queen Elizabeth II was not officially informed for nearly a decade that Anthony Blunt was a Soviet spy, newly declassified documents reveal.