The rebellion against Sir Keir Starmer intensified on Wednesday as more than a dozen Labour MPs tried to force a Commons vote on a ceasefire in Gaza.

A group of backbenchers from the Left wing of the party, including former shadow cabinet ministers, have tabled an amendment to the King’s Speech that calls on the Government to press for a truce.

Their move will be seen as a challenge to the authority of Sir Keir, who has refused to bend to calls from within his party to back a ceasefire.

It came hours after Imran Hussain, a shadow levelling up minister and MP for Bradford East, became the first frontbencher to resign over the issue.

Labour bosses will now fear an exodus of junior frontbenchers, although it is not thought that any of the shadow cabinet are close to quitting.

Sir Keir has been hit by a huge rebellion, with 18 frontbenchers and more than 40 backbench MPs defying his stance and pressing for a truce.

He has insisted that ending the fighting now would only benefit Hamas, leaving the group in a position where it could carry out further terrorist attacks.

Instead he is pushing for agreed “humanitarian pauses” in the fighting to allow aid into Gaza, although many of his MPs feel that position does not go far enough.

If selected by the Speaker, the Labour rebels’ amendment to the King’s Speech would be debated next week.

It describes Israel’s actions as “collective punishment of the Palestinian people” and expresses “alarm at the Israeli military’s total siege and bombardment of Gaza”.

The amendment, which also condemns the Hamas terror attacks of Oct 7, calls on the Government “to urgently press all parties to agree to an immediate ceasefire”.

Any vote on the amendment would be hugely problematic for Sir Keir, raising the prospect of dozens of his own MPs, including some frontbenchers, voting against him.

The rebels include a number of former shadow cabinet ministers including John McDonnell, Richard Burgon, Rosena Allin-Khan and Rebecca Long-Bailey. Jeremy Corbyn, the former Labour leader, who remains popular amongst grassroots activists on the Left, has also signed the amendment.

A spokesman for Sir Keir said he “fully understands calls for a ceasefire” but insisted he would not be backing down from his position.

“Everybody wants to see an end to the shocking images we are seeing in Gaza. We need to see all hostages released and aid getting to those most in need,” he said.

“But a ceasefire now will only freeze this conflict and would leave hostages in Gaza and Hamas with the infrastructure and capability to carry out the sort of attack we saw on Oct 7.

“International law must be followed at all times, and innocent civilians must be protected. Labour is calling for humanitarian pauses in the fighting. This is the best and most realistic way to address the humanitarian emergency in Gaza and is a position shared by our major allies.”