Britain’s Labour Party leader Jeremy Corbyn has been forced to allow his members a free vote on airstrikes in Syria to stave off a revolt could have included members of his shadow cabinet.

Corbyn’s spokesman said on Monday that top opposition lawmakers had “accepted his recommendation” of a free vote.

Prime Minister David Cameron, who leads the ruling Conservative Party, made his case for British airstrikes against the self-declared Islamic State in Syria last week after the group had claimed responsibility for a series of terrorist attacks in Paris that left more than 130 dead.

“If not now, when?” he asked.

Not convinced

But Corbyn, who led the Stop the War Coalition against Britain’s participation in the invasion of Iraq before he became leader, said that Cameron had not yet “made a convincing case” for airstrikes.

The Independent newspaper reports that only three out of 31 shadow ministers share his view.

One lawmaker said that if Corbyn were to impose his view on the party, it would “destroy” Labour.

British jets are currently bombing Islamic State positions in Iraq at the invitation of the government in Baghdad. They are barred from operating over Syria where the group is also active. American and French jets do fly there.

Corbyn was elected party leader in September with 60 percent support, but only a handful of lawmakers supported him.