Jeremy Corbyn, the new leader of Britain’s opposition Labour Party takes part in his first Prime Minister’s Questions in the House of Commons in Westminster, London, September 16, 2015.

Senior members of Britain’s opposition Labour Party are planning to defy their new leader and vote with the government to carry out air strikes against ISIS in Syria, the Sunday Times newspaper reported.

The paper said that half of the party’s shadow cabinet would side with Prime Minister David Cameron’s Conservative government in a House of Commons vote it said could be held next month.

Britain is already taking part in U.S.-led air strikes against ISIS in Iraq and the government wants to extend the campaign to Syria but has said it will ask for parliamentary consent.

“There is a majority in the Commons for air strikes in Syria if Cameron has a proper plan for targeting Isis,” a shadow cabinet member told the paper, using another acronym for the militant group.

“You would get half the shadow cabinet supporting it,” the senior Labour official was quoted as saying.

The party’s newly-elected leader Jeremy Corbyn on Saturday resigned his role as chairman of the Stop the War campaign group that he helped found but restated his anti-war stance.

“In stepping down as chair, I want to make absolutely clear my continuing solidarity with the coalition and its work against wars of intervention,” Corbyn said in a statement.

“It is now my job to lead the Labour Party, including in the struggle for peace and international justice, and that is demanding my undivided attention.”

Stop the War was originally set up to oppose U.S.-led intervention in Afghanistan following the September 11 attacks and went on to organize Britain’s biggest ever rally against the 2003 invasion of Iraq.