The prime minister is under growing pressure from Tory backbenchers over the Partygate scandal, with some MPs predicting he will face a leadership contest once the investigation into drinks gatherings is published.
Conservative peer Lord Heseltine appeared to suggest that Mr Johnson’s exit as a result of the current public “anger” could lead to a second referendum on Brexit.
The senior Tory, who is a leading campaigner for another vote on EU membership, told Times Radio: “The Brexit agenda was a pack of lies ... What happens if Boris goes, does Brexit go – throw the whole thing up in the air?”
The former deputy PM added: “Will the majority, now, of people who believe Brexit was wrong have another chance to express their view?”
Lord Heseltine warned that the public mood was febrile, and called for the Tory leadership question to be “resolved quickly”.
He said: “People are extremely angry, and they turn to extremes in those circumstances, we know, with horrific consequences in history. So something has to be resolved quickly.
“This is against the background where the government is going to be less popular, for one reason, and that is the falling living standards that are now built into the inflation cycle.”
Earlier on Thursday, former Labour prime minister Sir Tony Blair said it would be a mistake to start campaigning for EU membership any time soon.
Asked whether he would want Britain to rejoin the bloc in future, Sir Tony said: “It would be a political error to revive the whole argument – you just have to accept that, no matter how passionately opposed to it I was.”
He said the focus should be on making the relationship with the EU “work”, adding: “You don’t want a situation where your prime minister is not on good terms with European leaders.”
Labour leader Sir Keir Starmer said this week that he had ruled out a return to the single market or the customs union. “There’s no case for rejoining, so we have to make it work. We are out and we’re staying out,” he told The Guardian.
Meanwhile, senior Tory Brexiteer Steve Baker said on Thursday that it looked like “checkmate” for Mr Johnson, suggesting that his time at No 10 was coming to an end.
Fellow Brexiteer MP Andrew Bridgen – one of seven MPs to have publicly declared that they want Mr Johnson to go, and that they have submitted no-confidence letters – has predicted that a vote will take place next week.
To trigger a leadership challenge, 54 Conservative MPs must write letters of no confidence to the chair of the backbench 1922 Committee. A simple majority of Tory MPs – around 180 – would then have to vote against Mr Johnson in order to spark a leadership contest for a new prime minister.
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