Sir Malcolm Rifkind, who leads the body that oversees the work of the intelligence services, said the organisations had „serious questions to answer“. The MI5 chief, Andrew Parker, will provide a written report on the incident this week, before he is called before the Intelligence and Security Committee (ISC).

But Sir Malcolm, who is chairman of the ISC, pledged that the committee would also use new powers to force intelligence agencies to hand over all confidential documents relating to the case.