David Cameron is expected to make a statement this evening on the next steps on airstrikes in Syria, after Labour MPs were told they can vote with their consciences on military action.
Labour leader Jeremy Corbyn's decision to allow his MPs a free vote appears to clear the way for the Prime Minister to seek the approval of the House of Commons for extending RAF bombing missions against the Islamic State terror group from Iraq into Syria.
A two-hour meeting of the shadow cabinet heard that as many as 43% of Labour MPs - almost 100 of the 231-strong parliamentary party - back airstrikes, against 57% - around 132 - who would follow Mr Corbyn into the No lobby.
If correct, this would provide Mr Cameron with the "clear majority" he wants to avoid a repeat of his defeat in 2013, when he sought approval to launch action against the regime of Syria's president Bashar Assad.
A senior Labour source said both Mr Corbyn and shadow foreign secretary Hilary Benn will speak from the despatch box in the Commons debate, even though they would vote in opposite directions, but denied the party's position was "shambolic".
Labour is pushing for a two-day debate which the party said should not be held until next week at the earliest, and is calling on Mr Cameron to also allow Conservative MPs a free vote.