MPs must unite behind Theresa May’s Brexit deal or see the UK take “a path of deep and grave uncertainty”, the Prime Minister has said. 

As the PM sought to face down backbenchers demanding a vote of no-confidence, May said the draft deal she published on Wednesday recognised “inescapable” truths in the negotiations. 

She said “difficult and sometimes uncomfortable decisions” were made during negotiations, adding, in a pointed message to critics in her party, “If we do not move forward with that agreement nobody can know for sure the consequences that will follow. 

“It would be to take a path of deep and grave uncertainty when the British people just want us to get on with it. 

“They are looking to the Conservative Party to deliver.” 

The PM faced the cameras on a day of high drama in Westminster, with speculation mounting that a challenge to her leadership was imminent. 

A string of resignations, including that of Brexit Secretary Dominic Raab and Work and Pensions Secretary Esther McVey, rocked the government. 

Reports were circulating that Environment Secretary Michael Gove could soon follow. 

Influential Brexiteer Jacob Rees-Mogg, chairman of the European Research Group, has also revealed in a snap press conference he had written a letter calling for a no-confidence vote in the PM, with many of the 70-strong faction rumoured to be ready to follow suit. 

At the press conference inside No 10 Downing Street, the beleaguered PM was asked if she would survive a challenge to her leadership, to which she replied: “I believe this is a deal which does deliver that, which is in the national interest and am I going to see this through? Yes.”

She also compared herself to the cricketing hero Geoffrey Boycott, for his refusal to give up, telling reporters: “What do we know about Geoffrey Boycott? Geoffrey Boycott stuck to it and he got the runs in the end.”

It is not yet clear how many more letters are still needed to hit the 1922′s committee threshold of 48 to spark a contest, but Brexit-backing MPs reacted with fury in the wake of the publication of the draft deal on Wednesday night. 

They say keeping the UK in a customs union as a backstop arrangement – something which cannot be unilaterally ended by the UK – amounted to a “capitulation” to Brussels. 

Former Brexit minister Steve Baker is among a number who have called for a leadership challenge. 

DUP MPs, meanwhile, said they cannot support the deal as it allows for differing regulations in Northern Ireland and accuse the PM of a betrayal. 

May said, however, that there was no Brexit deal that would not include a backstop. 

In a separate development, she had earlier told MPs: “We can choose to leave with no deal, we can risk no Brexit at all, or we can choose to unite and support the best deal that can be negotiated.” 

Her assertion that “no Brexit” was on the table was not only seized on by hardcore Remainers and those backing a so-called people’s vote but by politicians in Brussels. 

European Council president Donald Tusk told a news conference in the Belgian city: “The EU is prepared for a final deal with the United Kingdom in November. 

“We are also prepared for a no-deal scenario but of course we are best prepared for a no-Brexit scenario.”