Boris Johnson is under mounting pressure to quit the fractious race for Prime Minister after a leading Tory said he is a "guaranteed disaster" who will "implode".
Steve Baker, an influential right-wing Brexiteer who backed Mr Johnson in 2019 and Liz Truss this year, launched a blistering attack on the former premier's comeback bid and backed Rishi Sunak instead.
Speaking on Sky News, Mr Baker said Mr Johnson "is a guaranteed nailed-on failure” and "he’s bound to implode, taking the whole government down with him”.
“ Boris Johnson would be a guaranteed disaster,” the Northern Ireland minister added, and "I'm not willing to lay down my integrity for Boris Johnson".
Warning of the Privileges Committee, which will rule on whether the PM lied to Parliament, he added: "When that vote comes, and it will, his premiership will implode".
Boris Johnson and Rishi Sunak were locked in secret talks on Saturday night to strike a deal over the next Prime Minister.
The duo arranged to chat at about 3.30pm, but it was unexpectedly pushed back to 5.30pm, then around 9pm, according to reports.
A senior Tory told the Sunday Times it was "like getting pandas to mate". The talks were said to have finally broken up after 11pm.
Multiple sources close to the two men refused to comment on the talks and details were scarce as dawn broke on Sunday.
Boris Johnson backers fuelled speculation of a deal after the late-night-talks - and a series of blows to the former PM's bid for power.
Supporter John Whittingdale told Times Radio: "If an agreement is reached, then I will be very happy and pleased to support it." Former chief whip Chris Heaton-Harris added: "If they came together, I think it would be a dramatic turn for the better for us all."
Mr Heaton-Harris added: "I will be speaking to Boris quite shortly."
Penny Mordaunt backer Damian Green warned Sky News: “If it’s all stitched up behind closed doors by big figures at Westminster, our party members will feel cheated.”
But in a bombshell intervention, Boris Johnson is thought to have told backers on an 8am call that there was no deal and he would not back down.
Johnson supporter Jacob Rees-Mogg appeared to confirm this, telling the BBC : "I have been speaking to Boris Johnson, and clearly he's going to stand, there's a great deal of support for him".
And ex-Chancellor Nadhim Zahawi suggested Boris Johnson was still fighting on by backing him at 9.30am. He claimed the ex-PM "got the big calls right" and "Britain needs him back. We need to unite to deliver on our manifesto."
The two Tory MPs are the frontrunners in the race to lead their party, and ultimately become the new PM.
If two or more candidates get 100 MP backers by 2pm on Monday, they will go to a run-off vote of Tory members to choose a new PM by Friday. But there is pressure for a deal for one man to drop out, "crown" the other and avoid more Tory splits.
Rishi Sunak has more support among MPs but Boris Johnson's backers believe he would win if it goes to a vote of party members.
Steve Baker suggested Boris Johnson could be a "chairman" of the Tory party. The former head of backbench Brexiteers told Sky's Sophy Ridge On Sunday: "I think it would be for the best if Boris did something big and statesmanlike.
"What we can't do is have him as prime minister in circumstances where he's bound to implode, taking down the whole government with him."
He went on: "I'm afraid the trouble is because of the (Commons Privileges Committee) vote, Boris would be a guaranteed disaster.
"There's going to be a vote before the House of Commons on this issue of privileges, whether he will deliberately misled the house.
"In that vote it's guaranteed there'll be a large number of Conservatives who will refuse, as they see it, to lay down their integrity to save him, and at that moment his premiership will collapse."
He added: "It's a guaranteed nailed-on failure and we cannot allow it to happen."
The disgraced former premier jetted in yesterday from his Caribbean beach holiday after telling allies he was “up for” the leadership battle against Rishi Sunak and Penny Mordaunt.
By mid-afternoon he appeared to have stalled on just over 50 publicly-declared nominators - far short of the 100 needed by 2pm on Monday to get on the ballot - despite six Cabinet ministers and Priti Patel swinging behind him.
But in a surprise move his former parliamentary aide, James Duddridge, tweeted just before 3pm on Saturday: “New - Boris Johnson has more than 100 backers”.
That was despite a string of key former allies - Lord Frost, Dominic Raab and Steve Barclay - disowning Mr Johnson this morning and backing his rival Rishi Sunak instead.
Tory MPs who back Rishi Sunak voiced doubt over the '100 Johnson backers' claim - pointing out MPs can say one thing privately and do another in the election.
One Sunak-backer branded the claim "completely desperate" and suggested it was made up to keep momentum up for Mr Johnson. "Desperate move as it can easily backfire," they added.
Labour MP Chris Bryant retorted: "Name them."
Tory MP Richard Holden, a Sunak backer, retweeted a GIF of Alan Partridge saying "I've got 104 friends".
Te ex-PM's dad Stanley predicted his son "will put his name forward", and added as a Tory member he will personally vote for him.
Mr Johnson Senior told GB News "he believes there are things to do still” and despite lucrative speaking offers, “he’s ready to give those temptations up to endure the slings and arrows” of leadership.
Liz Truss resigned on Thursday after just 44 days in office, becoming Britain’s shortest-serving PM in history.
She lasted less time than the B&Q returns policy, Cher's Believe staying at No1 in the charts, or magician David Blaine’s stint living in a box after she unleashed chaos on the mortgage market with £70bn in unfunded tax cuts.
If Mr Johnson were to drop out of the race, or fail to reach 100 backers, Rishi Sunak could be “crowned” Prime Minister as soon as Monday night or Tuesday morning.
Backings for Rishi Sunak continued to trickle in throughout Saturday but only a handful added to Penny Mordaunt's tally of just over 20 - suggesting she would have to drop out.
Ms Mordaunt today said she had been encouraged by the support she had received from fellow Tories and wanted to unite the party. She also assured Jeremy Hunt he could stay on as Chancellor if she won.
