BORIS Johnson has been warned that if he ignores votes at Westminster to pass a law to block a no-deal Brexit, then it would be a “full-blown attack” on the British constitution.

The warning from Labour came after Michael Gove refused to confirm the UK Government would abide by legislation blocking a no-deal Brexit if it were forced through by Tory rebels and the Opposition.

Ahead of what promises to be an historic parliamentary showdown this week, the Cabinet Office Minister knocked back fears of food shortages in a no-deal outcome but admitted that some food prices would increase if the UK crashed out of the EU without a deal on October 31.

Pressed repeatedly on whether the Government would abide by a successful bid by Commons opponents to pass legislation preventing a no-deal withdrawal at Hallowe’en, Mr Gove told BBC One's The Andrew Marr Show: "Let's see what the legislation says. You're asking me about a pig in a poke. And I will wait to see what legislation the opposition may try to bring forward."

Mr Gove added: "For me, the most important thing is to bear in mind actually, we already have legislation in place which an overwhelming majority of MPs voted for.

"We already have an EU Withdrawal Act, we already have the notice on Article 50, the process by which we leave the EU."

But the comments drew a response of anger and dismay from political opponents.

Sir Keir Starmer, the Shadow Brexit Secretary, described Mr Gove’s comments as “breath-taking,” and demanded the Prime Minister make a statement of clarification. “No Government is above the law,” he declared.

His Labour colleague, Jon Trickett, the Shadow Cabinet Office Minister, said: "Boris Johnson has shown his contempt for our democracy and the British people. Any move to ignore an act of Parliament would be a full-blown attack on our constitution.

"It is staggering that in the same interview, Michael Gove admitted that the no-deal Brexit the Government is attempting to ram through will hit people’s living standards with increased food prices.

“This is a price that Boris Johnson is willing to pay because it won’t be him and his wealthy friends paying it but ordinary families already struggling after nine years of austerity.”

Mr Trickett added: "It is the people, not an unelected prime minister in hock to the vested interests of the richest, who should determine our country’s future."

Pete Wishart for the SNP said: "The Tories are jumping up the dictatorial scale at an alarming rate, bounding from plans to suspend Parliament and now refusing to say if they will abide by the law. It is clear that this government’s gone rogue. 

“How anyone can have a shred of confidence in this hapless boorach is utterly astounding - no one is above the law, and for Boris Johnson’s government to act like they are is genuinely terrifying for our democracy," added the Perth MP.

Guto Bebb, the former Conservative minister, said the Government’s “unprecedented willingness to flout the rules is a disgrace to our democracy”.

The Welsh backbencher went on: “Not only are they suspending Parliament to try and force through a disastrous no-deal but now they are suggesting that, even if Parliament passed a law requiring the Government to avoid no-deal, they might simply ignore it.

“Our very democracy is now under threat from Boris Johnson and his government,” claimed Mr Bebb.

He said Mr Gove had recently admitted that no-deal was not what he had campaigned for in 2016 but that he was now “willing to tear up our democratic system to force this outcome on the country against the wishes of both Parliament and the public”.

Mr Bebb, on behalf of the People’s Vote campaign, added: “The Brexiters in Government like to cloak themselves in the language of democracy but they willingly ignore basic democratic principles as and when it suits them.

“The British people should not and will not stand for it. It's no wonder the outrage and protests across the UK are growing larger all the time. The British people believe in democracy and fair play and the only way to resolve the Brexit crisis is to give them the final say.”

Meanwhile, David Gauke, the former Justice Secretary and a leading Tory rebel, made clear he would be prepared to give up the Conservative whip to block a no-deal in the national interest.

He told Sky’s Sophy Ridge on Sunday: “If it is the position now that defying the whip on a European vote is a matter that you lose the whip from the Conservative party, then there are quite a lot of Conservative MPs who over the recent months would have lost the whip.

“But sometimes there is a point where you have to judge between your own personal interests and the national interest and the national interest has to come first. But I hope it doesn’t come to that. I hope cooler and calmer heads will look at this and think that trying to split the Conservative Party in this way is not a sensible way forward for the Conservative Party, or indeed for the country," he added.

It has been suggested that as many as 20 Tory rebels are prepared to defy Mr Johnson and vote to block a no-deal outcome.

On Monday, Mr Gauke and former Cabinet ministers are set to have their own private showdown with the PM in Downing St.

"I want to hear from him as to what is his plan to deliver a deal. When are we putting forward proposals to deal with this backstop issue? And I want to hear how he plans to deliver the legislation if we get a deal by October 31, because at the moment, frankly, I can't see how he's got time to do that," said Mr Gauke.

Reports suggested that any Tory MP who defies the Government could see their candidacy withdrawn in the event of a snap general election. No 10 made clear “all options for party management are under consideration”.

International Development Secretary Alok Sharma told Tory rebels to be "clear whose side you are on".

In a warning to Conservative colleagues who are considering joining Opposition attempts to pass legislation to block a no-deal Brexit, Mr Sharma said they needed to "stand with the people" and deliver Brexit.

Speaking to Sky News, Mr Sharma said: "You need to be very clear whose side you are on."

On Marr, Mr Gove was pressed on whether or not there would be shortages of fresh food as a result of a no-deal Brexit. He replied: "Everyone will have the food they need," and then added: "No, there will be no shortages of fresh food."

Asked if food prices would increase, the Scot replied: "There are a number of economic factors in play. Some prices may go up. Other prices will come down."

Elsewhere, Labour’s John McDonnell said Mr Johnson and his government were "insulting the intelligence of the British people" in their explanation for suspending Parliament for up to five weeks until mid-October.

Describing the Tory leader as behaving like a “dictator,” the Shadow Chancellor declared: "Just because a Prime Minister is worried that they'll lose a vote in Parliament, to then use the tactic of closing down Parliament, in our parliamentary democracy, is unacceptable."