Rishi Sunak has criticised Lindsay Hoyle for how he handled the chaotic Gaza ceasefire vote as pressure grows on the Speaker to resign.

In his first public comments on the row, the prime minister said Hoyle should not have upended the “usual processes” of parliament in the face of “intimidation or aggressive behaviour”.

Hoyle has faced accusations of bias after up-ending parliamentary procedure by selecting a Labour amendment to an SNP motion calling for an “immediate ceasefire” in Gaza.

That had the effect of preventing what was expected to be a major rebellion by Labour MPs who had planned to vote with the SNP.

Stephen Flynn, the SNP leader in Westminster, has accused the Speaker of pro-Labour bias and said his party no longer has confidence in him remaining in post.

Hoyle has said one of the reasons he allowed Labour’s amendment was to protect MPs who faced a backlash from pro-Palestine campaigners if they failed to vote for a ceasefire

He said: “I have a duty of care, and if my mistake is looking after members, I am guilty.”

But Sunak said today: “What happened in the House of Commons last night is very concerning.

“It seems that the usual processes and the way that the House of Commons works were changed.

“Now my understanding is that the Speaker has apologised for that and is going to reflect on what happened.”

The prime minister added: “I think the important point here is that we should never let extremists intimidate us into changing the way in which parliament works.

“Parliament is an important place for us to have these debates. And just because some people may want to stifle that with intimidation or aggressive behaviour, we should not bend to that and change how parliament works. That’s a very slippery slope.”

Some 66 Tory and SNP MPs have so far signed a motion of no confidence in the Speaker as he continues to fight to save his job.

One former cabinet minister told HuffPost UK: “MPs are very divided on what should happen, but Lindsay does have enough Conservative support to win a vote of confidence if it comes to that.”