He is also facing a testing “end of term” meeting with fractious backbenchers when the 1922 committee convenes on Wednesday afternoon. 

Allies said that – with gossip about leadership challenges in the air – Mr Johnson had to hold his hands up over the recent rows over Downing Street parties and promise to put matters right.

He will also have to convince backbenchers that the Covid restrictions, which are intended to have a “sunset” at the end of next month, will not be continued any longer than necessary.

One backbencher said it was vital that Mr Johnson showed he was “listening” to concerns at the meeting, a day before a possible defeat in the North Shropshire byelection.

Mr Johnson’s authority as Tory leader and Prime Minister is being questioned openly as never before.

In a revealing interview, Chris Green, a Red Wall Tory MP, could not tell his local radio station that he backed Mr Johnson. Asked whether he “had confidence” in the Prime Minister personally, there was a six-second pause. “That’s a big question,” Mr Green said. Asked again, he said: “I think the silence does speak volumes.”

On Friday, one normally loyal Tory MP said of Mr Johnson: “He is in a death spiral. It is the beginning of the end for him.”