Theresa May will tell MPs today that there is no Plan B for Brexit, warning them that if they rejected her deal, she was “absolutely certain” they would not get a better one from Brussels.

The Prime Minister’s bold declaration comes after Jean-Claude Juncker, the European Commission President, sought to put his own pressure on MPs by saying that the UK-EU agreement on Brexit was the “only deal possible”.

The European Commission President cautioned: “Those who think by rejecting the deal that they would have a better one will be disappointed in the first seconds after the rejection of this deal."

EU leaders also emphasised the point with the Irish Taoiseach Leo Varadkar declaring: "There isn't a Plan B. What's being put in front of EU parliament and House of Commons is a deal. Any other deal really only exists in people's imagination."

And as Mrs May prepares to launch a two-week PR blitz, travelling up and down the country to sell the UK-EU Brexit deal over the heads of MPs to voters directly, Jeremy Hunt issued a clear warning to his Conservative colleagues that a rejection of the PM’s plan could end Tory rule.

Asked if such a rejection might collapse the Government, the Foreign Secretary replied: "It's not possible to rule out anything."

In her post-summit Brussels press conference, Mrs May refused to be drawn on whether she would stand down if she lost the Commons “meaningful vote,” despite being repeatedly pressed on the issue.

"I am focusing on ensuring that I make a case for this deal to MPs," she insisted.

This morning, the PM will chair Cabinet ahead of a Commons statement when she will seek to tell MPs what she believes are some home truths as they prepare for the crunch vote expected to take place early in the week beginning December 10.

Noting how the 525 days of complex negotiation had “required give and take on both sides,” Mrs May will declare: “I can say to the House with absolute certainty that there is not a better deal available. My fellow leaders were very clear on that themselves yesterday.”

She will again stress the need for MPs to “listen to our constituents and decide what is in our national interest”.

The PM will say: “There is a choice which MPs will have to make. We can back this deal, deliver on the vote of the referendum and move on to building a brighter future of opportunity and prosperity for all our people.

“Or this House can choose to reject this deal and go back to square one…[which] would open the door to more division and more uncertainty, with all the risks that will entail.”

Mrs May will insist the national interest is clear. “The British people want us to get on with a deal that honours the referendum and allows us to come together again as a country whichever way we voted. This is that deal; a deal that delivers for the British people.”

Responding to the EU27's endorsement of the Brexit Plan, which took just 38 minutes, Jeremy Corbyn denounced it as a “bad deal” for Britain and confirmed Labour would be voting against it.

"It is the result of a miserable failure of negotiation that leaves us with the worst of all worlds," argued the Labour leader.

Nicola Sturgeon, who described as “desperate” Mrs May’s weekend letter to the nation, explaining her Brexit Plan, tweeted: “This is a bad deal driven by the PM’s self-defeating red lines and continual pandering to the Right of her own party. Parliament should reject it and back a better alternative - SM/CU or #PeoplesVote.”

The First Minister also took to social media to say that she would be “up for a full leaders’ debate on the ‘deal,’” asking: “So, how about it PM @theresa_may?”

The Herald approached Downing Street for a response but failed to get one.

In other developments:

  • Labour and the SNP will this week hold talks at Westminster to see if they can agree on an alternative option should Mrs May’s Brexit Plan be voted down by MPs;
  • Tony Blair, the former PM, claimed another referendum was "the only way you are going to unite the country";
  • The DUP’s Arlene Foster said her party’s confidence and supply arrangement with the Tories was still “live” but insisted there was “no need for the Irish backstop, so let's get rid of it";
  • French President Emmanuel Macron suggested the EU would use its desire to get full access to UK waters for its fishermen as “leverage” in the future trade deal talks;
  • Spanish premier Pedro Sanchez signalled his government would make a fresh push for Gibraltar during the future UK-EU trade talks at the end of which each of the 27 member states would have a veto
  • On Tuesday, the European Court of Justice is to rule on whether the UK Government can unilaterally decide to end the Article 50 process and keep Britain in the EU.

In his post-summit press conference, Mr Juncker expressed his sadness at Britain’s decision to leave the EU bloc but suggested that the post-Brexit relationship would remain a very close one.

Noting how "divorce is a tragic moment," the Commission President added: "I don't think Britain will be a third country like other third countries are third countries. There is, between us, something which has the remainings of love."