A Devon MP has submitted a letter of no confidence in the Prime Minister.
Anthony Mangnall, who represents South Devon, has become the eleventh MP - that is publicly known - to submit a letter to the 1922 Committee of Conservative backbenchers.
It comes as the Prime Minister faces a police investigation into a number of parties it is claimed took place at Number 10 - including in his private flat - during the coronavirus lockdowns.
The revelations, which included claims of a birthday party for the Prime Minister held in the Cabinet Office, have seen a number of MPs call on him to go.
Announcing his decision, Mr Mangnall wrote: "Standards in public life matter.
"At this time I can no longer support the PM.
"His actions and mistruths are overshadowing the extraordinary work of so many excellent ministers and colleagues.
"I have submitted a letter of no confidence."
Should 54 letters be submitted to the committee chair - Graham Brady MP - it would prompt a confidence vote among Tory MPs, with Boris Johnson needing to secure the support of half of that group, plus one, to survive.
If he failed, it would trigger a leadership contest and he would be barred from standing.
East Devon MP Simon Jupp has not commented on the controversy.
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