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

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.

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.

Sir Anthony Blunt, the surveyor of the Queen's pictures and distinguished art historian, finally confessed he had been a Soviet agent since the 1930s.

The identity of a Russian spy among Queen Elizabeth II's courtiers was kept from the monarch for almost a decade, but she took the news with her typically calm demeanour

Queen Elizabeth II was kept in the dark for a long time about a major scandal during her reign. Newly released MI5 files reveal that, for nearly 10 years, the late monarch didn’t know that royal household member Anthony Blunt was actually a Soviet double agent.

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.

Newly released documents from British intelligence reveal new secrets about the late queen’s former art adviser.