David Cameron knew UK pilots were involved in US-led bombing missions of Isis targets in Syria, even though parliament had expressly rejected British military involvement in the country in 2013.
The prime minister’s spokeswoman said on Friday that up to a dozen pilots had been involved since September, but they were not operating under a British chain of command. “The PM was aware that UK personnel were involved in US operations and what they were doing.”
Details of British personnel’s involvement in strikes by allied nations’ forces were revealed by a freedom of information request by the pressure group Reprieve.
The House of Commons voted against military action in Syria in 2013, although at that time the targets envisaged were President Bashar al-Assad’s military forces. Parliamentary authorisation has only been given for UK air strikes against Isis in neighbouring Iraq.
Cameron and the defence secretary, Michael Fallon, made clear they were considering extending the military air campaign to Syria after the Tunisian beach massacre on 26 June, in which 30 Britons were among the 38 people killed. The pair have indicated that they would seek MPs’ approval for an extension of air strikes into Syria, but no vote is expected before autumn.
On Thursday the defence minister Lord Howe issued a lengthy written statement setting out the scale of British military operations in Syria and Iraq, making reference to UK air-to-air refuelling and reconnaissance over Syria, and the number of bombing raids in Iraq. It made no reference to British pilots dropping bombs in Syria.
The Speaker, John Bercow, is certain to grant an urgent statement to MPs requiring ministers to explain whether they have misled the house, or acted in breach of a parliamentary resolution.
The prime minister’s spokeswoman said the British aircrew were acting within international law and were merely carrying duties as part of an exchange with allies. She said it was well-known that the UK was in the lead as one of the anti-Isis coalition forces.
British forces had been embedded with their French counterparts on military operations since the 1950s, she said, and it was a way of retaining close military alliances, as well as provide valuable experience.
She declined to reveal whether Labour’s interim leader, Harriet Harman, had been told of the Syrian involvement when she was briefed by Cameron and defence chiefs on Tuesday at a specially convened meeting of the national security council.
The government is waiting for Labour to elect a new leader before appealing to the party to support open British involvement in bombing raids in Syria. The new leader is likely to accede to the request, but there is bound to be anger within Labour about whether Cameron should have been more open about the existing involvement.
Speaking on Sky News, Burnham said the government needed to “proceed cautiously and responsibly”. He said it should learn the lessons of the past where Britain staged military intervention “without perhaps the right evidence and the right justification”.
Tim Farron, the new leader of the Liberal Democrats, said the UK air strikes in Syria would “play into the hands” of Islamist militants waging jihad in the wartorn country and neighbouring Iraq.
He told Sky News on Friday morning: “My sense is that here, in the Isis-occupied territories of Syria and Iraq, for the UK and the US to be seen to be directly involved – particularly in Syria – just plays into the hands of the Islamic fundamentalists who abuse Islam and indeed murder so many Muslims and so many other people in and around their territories. Let’s not play into their hands.”