Isis will only be defeated by regional powers in the Middle East, John McDonnell has said. However, he said the Labour party wouldn’t make any decision on how to vote before hearing David Cameron’s proposals.

This morning the shadow chancellor appeared on the Andrew Marr show, he said Labour hadn’t yet decided whether there would be a free vote on airstrikes against Isis in Syria. McDonnell said the issue had to be debated by the shadow cabinet and then it would be discussed with the Parliamentary Labour Party.

McDonnell said that the party needed to see what David Cameron’s plan is before making any decisions, a sentiment also echoed by Labour’s deputy leader Tom Watson. This comes after a United Nations resolution calling for action against Isis by any and all means.

Next week Cameron will outline his case for the UK taking part in the bombing campaign against Isis in Syria. The Prime Minister will address the foreign affairs select committee’s opposition to to airstrikes last month, in particular the concern that there is no no coherent international strategy for defeating Isis or ending the Syrian civil war.

Labour leader Jeremy Corbyn has expressed extreme doubts over the effectiveness of airstrikes. Yesterday he told activists “the dreadful Paris attacks make the case for a far more urgent international effort … to reach a negotiated settlement of the Syrian civil war – and end the threat from Isis.”

However, a number of backbench MPs, such as John Woodcock MP and Liz Kendall MP, have indicated that they might vote for airstrikes if it comes before the Commons. George Osborne said the vote will only be called when the Government are sure they will have the numbers needed for their plans to pass through the Commons.

McDonnell explained his concerns over airstrikes, saying that a bombing campaign plays into Isis’ narrative where UK and US involvement is painted as a “crusader invasion”. He also rejected comparisons with WWII reportedly made by Cameron who is thought to be telling MPs to act like “Churchill not Chamberlain”

The Shadow Chancellor urged for a more sophisticated approach to the situation and said that the vote should not take place on a party political basis. “On the ground Isil has to be defeated by the regional powers in the Middle East…That’s the most effective long term security we can get,” he said.

McDonnell also asked Osborne to “end the cuts to policing”. He said the Chancellor would have his support on this issue if he chose to reverse cuts, and that there would be “no political game playing” on such an important issue.

He also slammed the Government’s record on the economy, saying that Osborne’s plans are in “chaos”.