The House of Commons is today expected to authorise air strikes on Islamic State targets in Syria, at the end of a debate scheduled to last more than 10 hours. David Cameron’s cabinet yesterday unanimously approved the 11-point motion to be debated, which is expected to pass with a comfortable majority, after Jeremy Corbyn agreed to allow Labour MPs a free vote.

Mr Corbyn yesterday defended his decision not to impose a whip but issued a clear warning to Labour MPs that they could pay a political price if they vote in favour of military action.

“I am saying to every MP: you make up your own mind. There is no hiding place behind a whipping arrangement or not: your decision, on behalf of your constituents, whether or not we should commit British troops into yet another war in the Middle East with no endgame in sight, no proper plan in sight, a mythical 75,000-strong apparently unknown Free Syrian Army operation, which is also infiltrated by a lot of jihadist elements. We are going into a very dangerous situation altogether,” he told the BBC.

Mr Corbyn will open the debate for Labour, arguing against the motion, but his shadow foreign secretary Hilary Benn, who will make Labour’s closing contribution, will argue in favour of it. Acknowledging the deep divisions in the party over the issue, the Labour leader said the course advocated by Mr Benn would lead to the killing of civilians in Syria.

“His belief is that we can get rid of Isil [another name for Islamic State] by bombing them. My reply to him and everybody else that supports bombing: when you bomb a town like Raqqa – where there are several hundred thousand people living there, who may or may not wish to be under Isil control; indeed many are trying to escape from there – we are going to kill people.

“We are going to kill people in their homes by our bombs. I think we should be very careful about that,” Mr Corbyn said.

Unprecedented threat

Mr Cameron said although the motion was about what he called the necessity of taking military action against Islamic State in Syria as well as Iraq, it was part of a broader strategy.

“It’s about politics and diplomacy and humanitarian aid, all of which we need to bring to bear to bring peace to Syria, but to make sure we protect our national interest of fighting against this appalling terrorist organisation,” he said.

The motion deliberately reflects language in a resolution passed by Labour this year, which set out the conditions necessary for the party to support military intervention. Mr Cameron said he had been careful in preparing the way for air strikes, because the risk to the lives of service personnel was paramount in his mind.

Proper process