THE Morning Star can reveal that MI5 declined to censor a book about its bugging of the British communists’ HQ, partly for fear of drawing the Soviet Union’s attention to the Security Service’s “sensitivity on the subject.”

In a letter — dated February 1968 and made public today by the National Archives — to Michael Stewart, the then Labour government’s first secretary of state, MI5 said it had “covertly” obtained a typescript copy of double agent Kim Philby’s memoirs.

It pointed out that, according to Philby, Roger Hollis — head of MI5’s F division, which monitored political groups — had the Communist Party of Great Britain’s (CPGB) office in central London under constant state surveillance.