David Davis has said the Prime Minister has two options in order to salvage his political career, "a comparatively dignified exit" or "being thrown out on his ear".
Condemning the Prime Minister's recent handling of the allegations against Chris Pincher, the MP told GB News that "being elected Prime Minister is not an allowance to do anything you like, it doesn't allow you to break the law and it doesn't allow you to break the rules of democracy".
When questioned by GB News presenter Nigel Farage whether the Prime Minister's leadership had come to an end, Mr Davis replied: "I think it is, I mean i think wether its up in the next few days or the next few months."
Discussing the premiership of Margaret Thatcher, the MP compared the current situation to her downfall as Conservative Leader in 1990, saying: "In a way its a bit of a replica of what happened with Margaret, I mean she wasn't actually thrown out by the party, she got the majority vote, it was the men in grey suits."
The 1922 Committee held a meeting earlier this afternoon to discuss the future of the Prime Minister.
Deciding not to change the leadership election rules, an MP who attended the meeting told GB News reporter Tom Harwood that instead of a rule change, the committee has sped up the election process, with backbench MPs now set to vote on Monday instead of Wednesday.
Commenting on the gathering of the 1922 Committee, the MP acknowledged rumours of mounting letters of no confidence against the Prime Minister, saying:"There are rumours around that there are a lot more letters in, possibly 40 percent of the party, that they have been looking at changing the rules to allow that high level to trigger the new vote even inside the year and that of course."
The MP added: "If the prime ministers got any sense, he's then facing the choice between a comparatively dignified exit and being thrown out on his ear."
Nominations for a new leader would be open for Conservative MPs if Mr Johnson was defeated in a fresh confidence vote, with MPs potentially whittling the candidates down to the final two before the summer recess.