The MP for East Devon has called upon Boris Johnson to resign.

Simon Jupp has tweeted an open letter to his constituents saying he ‘no longer has confidence in the Prime Minister’ and Mr Johnson should ‘do the decent thing and resign’.

He continues: “If he does not, colleagues and I must consider how we can bring about a change of leadership at the earliest opportunity.”

Mr Jupp’s expression of no confidence is part of a growing revolt against Boris Johnson’s leadership, apparently triggered by his handling of the Chris Pincher controversy, when Mr Johnson claimed he had ‘forgotten about’ being told of previous allegations of “inappropriate” conduct.

Yesterday the Health minister Sajid Javid and chancellor Rishi Sunak dramatically resigned from their Government positions within minutes of each other.

This paved the way for a series of further departures – at least 21 Tories have quit Government or party positions, and other backbenchers have also withdrawn their support.

Yet today at Prime Minister’s Questions, Mr Johnson refused to resign and insisted that he would stay in office.

Over the past weeks and months, Mr Jupp has been criticised for his silence over the Partygate revelations and other controversies surrounding Mr Johnson’s leadership.

But today, in his letter, he said: “I cannot tolerate this any longer and my constituents in East Devon expect better.”