WESTMINSTER’S newly-formed security committee will not be able to investigate on-going military operations, David Cameron has told MPs, but it could investigate the recent RAF drone strike, which killed two British jihadists in Syria.

The Prime Minister told MPs he was happy to consider a probe by the parliamentary Intelligence and Security Committee(ISC) into last month's military operation in the Isis stronghold of Raqqah to eliminate suspected terrorists Reyaad Khan from Cardiff and Ruhul Amin from Aberdeen.

But with the UK Government making clear it would not hesitate to take similar action against others on a reported kill-list of Isis militants, he insisted he would not "contract out" responsibility for the UK's anti-terror policy to the ISC.

Critics have argued that any military action ordered without the prior approval of Westminster should be subject to a system of checks with some suggesting the ISC should play a role.

At PMQs, Mr Cameron was pressed on the issue by Angus Robertson, the SNP leader in the Commons, who has been chosen by MPs to serve on the ISC; the first Nationalist Member to do so.

The PM said he would be "very happy to discuss that with the new chair", who is still to be appointed but explained: "The only proviso I would put on is that the ISC cannot be responsible for overseeing current operations.

"The responsibility for current operations must lie with the Government and the Government has to come to the House of Commons to explain that. I am not going to contract out our counter-terrorism policy to someone else. I take responsibility for it.

“But it is important, after these events have taken place, that the ISC is able to make these sort of investigations."

Mr Cameron also made clear that removing President Bashar al-Assad and Isis would require “not just spending money, not just aid, not just diplomacy but it will on occasion require hard military force,” raising the possibility of further UK military action in Syria.

Asked about the drone strike during an appearance before the Commons Foreign Affairs Committee, Foreign Secretary Philip Hammond said: "The situation is that we have a very robust process for authorisation of any such action and then there is a whole set of rules of engagement once it moves to the military phase, which have to be complied with. There is a rigorous process for monitoring that and analysing outcomes."