Theresa May should resign immediately because her humiliating climbdown over her Brexit deal proves she has lost the confidence of parliament, Jacob Rees-Mogg has said.
The hardliner said it was “properly constitutional” that the prime minister go now “regardless of letters, votes of confidence or anything of that kind”.
It comes as speculation was mounting that the threshold for the number of letters from Tory MPs calling for a no-confidence vote in May’s leadership - 48 - has been reached.
Rees-Mogg, who leads the influential group of Tory Brexiteers the European Research Group (ERG), told HuffPost on Tuesday night that May had essentially admitted her deal would have lost by 100-plus votes and that her position was now unsustainable.
He said: “Yesterday, the motion was pulled because the prime minister could not get through the most major plank of her policy.
“That seems to me a loss of the confidence of the House. It seems to me that she ought to resign because of that, regardless of letters, votes of confidence or anything of that kind.”
Despite uproar among her backbenchers, Jeremy Corbyn has faced down calls by the SNP, Plaid Cmyru, the Greens and some of his own Labour MPs to trigger a vote of no-confidence in the government.
Labour has said there is no point forcing a no confidence vote until it can be won.
The prime minister, meanwhile, returned from Brussels on Tuesday night after holding talks with European leaders in a last-ditch attempt to win concessions.
In a further sign that a no-confidence vote could be imminent, chief whip Julian Smith was seen entering No 10 late on Tuesday night.
But when asked in Europe whether she was preparing for a no-confidence motion, May had brushed aside the prospect and told reporters: “I have been here in Europe dealing with the issue I have promised Parliament I would be dealing with.”
Whatever concessions she is able to secure are unlikely to satisfy her critics however.
The ERG has said it would reject the deal even if the Northern Irish backstop were removed, on the grounds of the £39bn divorce bill it compelled the UK to pay.
The DUP, meanwhile want the backstop to be wiped from the legislation, while May told reporters she was aiming to make any temporary customs arrangement time-limited.
“Whatever outcome we want, whatever relationship we want with the European Union in future, there is no deal available that doesn’t have a backstop within it,” May added.
Rees-Mogg, who spoke to HuffPost as he emerged from convening a meeting of the ERG in Portcullis House’s Thatcher Room, went on draw comparisons between May’s premiership to that of wartime Tory PM Neville Chamberlain.
Chamberlain faced a vote on the Norway campaign, a failed British-led bid by allied forces to repel Nazis in Scandinavia in the Second World War.
Chamberlain won the vote with a vastly reduced majority, but still chose to resign, paving the way for a national unity government led by Winston Churchill.
He said: “I can’t think of an occasion when a prime minister, having lost a vote of that kind, has remained in office. They are very rare.
“The Norway vote, of course, Chamberlain wins, but he still goes because the vote against him was so great.”
Rees-Mogg said the group had not got behind one candidate to replace May.
But he called for “a small number” of candidates to come forward, heightening speculation Tory MPs are gearing up to topple May and instal a new leader swiftly.
Eurosceptics are thought to be split between four big beasts - Boris Johnson, Dominic Raab, Esther McVey and David Davis.
Rees-Mogg said, however, that the candidates should face a vote of the membership to have any mandate.
He added: “Theresa May has always suffered from not having gone to the members, not having that mandate where she could say to me ‘I have the backing of all the members of the party’.”
In a Conservative leadership candidate, this would only happen if MPs fail to choose between a remaining two.
“I would expect there to be a number of candidates from the Eurosceptic wing of the party, but I won’t be one of them, because I think it is important that it’s a small number of realistic candidates,” he said.
“We don’t want a great winnowing of dozens of candidates. I don’t think there is time for that.”