John Bercow was at the centre of furious Commons scenes as MPs squabbled over the potential process of bringing forward a Brexit plan B.

The Commons Speaker faced a backlash from Conservative MPs after selecting an amendment from Tory former minister Dominic Grieve, which aims to ensure Prime Minister Theresa May returns with a revised EU exit plan within three sitting days if her original Brexit deal is defeated.

Mr Grieve’s amendment wants to speed up the process for a plan B and seeks to change a Government motion detailing the timetable for the Brexit deal debate, which Tory MPs argued was “unamendable”.

A vote is expected on Mr Grieve’s proposal and the Government could be defeated.

Mr Bercow stood by his decision, telling the Commons: “My understanding is the motion is amendable, I’m clear in my mind about that.”

After heckles from the Tory benches, he added: “I’m trying to do the right thing and make the right judgments. That is what I have tried to do and what I will go on doing.”

Tory former minister Mark Francois, deputy chairman of the Eurosceptic European Research Group (ERG), claimed Mr Bercow was not following his own rules.

Raising a point of order after PMQs, he said: “Mr Speaker, I have not been in this House as long as you but I have been here for 18 years and I have never known any occasion when any Speaker has overruled a motion of the House of Commons.

“You have said again and again you’re a servant of this House and we take you at your word, and I have heard you many times on points of order when people have challenged you say ‘I cannot do X or Y because I am bound by a motion of the House’.

“You have done that multiple times in my experience, so why are you overruling this today?”

As a furious Mr Francois yelled “ridiculous” and “that is utter sophistry”, Mr Bercow defended his decision.

“The answer is simple,” he said.

“He referred to a motion and he said that no motion in this context, for the purposes of precis, may be moved other then by a Minister of the Crown. ‘Tis so.

“We’re not speaking here of a motion but of an amendment to a motion. I’m sorry but there is a distinction between a motion and an amendment.

“What he says about a motion I accept but it doesn’t relate to an amendment. That is the answer.”

Commons Leader Andrea Leadsom noted there were “some concerns” about Mr Bercow’s decision and asked him to confirm that his decision was taken with “full advice” from the Commons clerk and other parliamentary advisers.

She asked him to publish the advice, which prompted cheers from Tory MPs.

Mr Bercow confirmed he consulted the clerk and officials, saying the advice was given to him “privately and that’s absolutely proper”.

He said: “It’s also true I had a written note from the clerk from which I quoted in responding to the first point of order.”

Tory MP David Morris (Morecambe and Lunesdale) leapt to his feet and repeatedly shouted: “Publish it!”

Mr Bercow added there was not full written advice nor a brief, and did not confirm that his decision was taken with agreement from the Commons clerk Sir David Natzler.

Conservative former cabinet minister Ken Clarke earlier said he found it “unbelievable” that some MPs were trying to stop the Commons expressing its opinion on the matter.

He said: “I would suggest to some of my honourable friends, the ones that are getting somewhat overexcited, that perhaps they should don a yellow jacket and go outside.”