There is "pretty compelling" evidence that Government listening post GCHQ is passing information to the US to help it locate targets for controversial drone attacks, it was claimed last night.
Former director of public prosecutions Lord Macdonald said the British people had a right to know if the agency was helping the US secret services to find al Qaida and Taliban targets in Pakistan.
Pakistan has repeatedly protested over the unmanned attacks claiming it is a "violation of its sovereignty and international law".
Lord Macdonald told The Times: "The evidence is pretty compelling that we are providing that kind of information to the Americans... The British people have a right to know about the policies being pursued by their Government."
He added: "I've been to Pakistan and I have seen what drone strikes can do. Innocent people do get killed as a result of misplaced strikes. It is also succeeding in creating a new generation of people with huge resentment against the West, fuelling the kind of terrorism we are trying to fight. The fact this is one-sided, mechanised and robotic gives these strikes a particularly sinister dimension."
It comes after reports that a GCHQ official admitted the agency was proud of providing "locational intelligence" to the CIA.
Lord Macdonald said: "If that is right, it strikes me as difficult for the Government to sustain the position that they are not going to comment. Presumably if GCHQ are saying that, then one presumes they are reflecting government policy in saying it."
Earlier this year David Anderson, the independent reviewer of terrorism legislations, warned the Government faces a raft of civil cases over possible complicity.
A Foreign Office spokesman said: "It's the UK's long-standing policy not to comment on intelligence matters."