14 (UPI) --Documents newly declassified by MI5, Britain's internal intelligence agency ... only told her about the infamous Cambridge Five member and art historian, Anthony Blunt, who was employed as the monarch's surveyor of official pictures, in 1973 ...

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.

Queen Elizabeth was left in the dark for almost a decade over the full scale of the treachery of one of her most senior courtiers, according to newly-released official files

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. The files about royal art historian Anthony Blunt are among a trove from the intelligence agency MI5 released on Tuesday (Wednesday AEDT) by Britain's National Archives.

Confessions of double agents and tips for new spies have been released as part of a tranche of recently-declassified documents from MI5. The documents are part of a new exhibition on display at the National Archives this spring and include details about some of Britain's most notorious spies.

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

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.