“I recognise this may be my last ministerial job,but I believe these standards are worth fighting for and that is why I am resigning.”

The pair did not co-ordinate their resignations and came to their decisions independently,they said.

Theirs make three resignations from cabinet in a fortnight.

Quince wrote he resigned because assurances he had received from Johnson the night before turned out to be inaccurate.

Oliver Dowden,an influential figurequit last month after two devastating byelection losses,saying someone had to take responsibility.

Conservative Party vice-chair Bim Afolami also quit his role,telling the BBC,“I think it’s become clear the time has come for[Johnson] to stand down”.

One senior MP toldThe Sydney Morning HeraldandThe Agethat it was “the beginning of the end” for Johnson.

Johnson ploughed on,appointing two others to replace them:his chief of staff,Steve Barclay,replaced Javid,and Nadhim Zahawi,the education secretary who is widely believed to be making a tilt for No.10 himself,replaced Sunak. Zahawi is now the third chancellor (treasurer) in as many years.

Javid and Sunak’s resignations began straight after Johnson went on television to apologise for appointing Chris Pincher to the deputy whip’s role despite concerns being raised about Pincher’s personal conduct.

Pincher quit as whip last Thursday after being accused of groping men while drunk.

Johnson said a complaint against Pincher had been raised with him in a manner that was “only cursory”,but that he regretted not acting at the time.

In a letter responding to Javid’s resignation,Johnson said he looked forward to the former health secretary’s contributions from the backbench.

Johnson still enjoys the support of the bulk of his cabinet for now. Foreign Secretary Liz Truss,widely considered to be gathering support to make a tilt,is backing the prime minister.

Opposition Leader Keir Starmer said it was clear the government was collapsing and called for an election.

“The Tory party is corrupted and changing one man won’t fix that,” the Labour leader said in a statement.

“Only a real change of government can give Britain the fresh start it needs,” he said.

Johnson faced an uncoordinated ousting attempt last month when the required number of MPs submitted letters of no confidence.

However,with no clear rival,he won the vote.

Backbencher Andrew Browne said that if Johnson did not resign,he must be removed.

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