Boris Johnson's actions over the Chris Pincher case are "tantamount to an effective cover-up of sexual abuse", a senior Tory MP has said.
In an irate letter of no-confidence former Conservative party vice chair Chris Skidmore said Tory rules needed to be changed to oust Mr Johnson as prime minister.
The latest Conservative broadside against the PM comes after over a dozen of his own MPs quit the government over Mr Johnson’s conduct.
"Recent events have revealed that the prime minister repeatedly was informed and knew about allegations of sexual misconduct and previously upheld complaints against a member of the government," Mr Skidmore wrote – referring to the handling of the Chris Pincher case.
"He [Mr Johnson] subsequently took the decision to promote this person into a position responsible for the welfare of Conservative Members of Parliament.
"In responding to these events, the Prime Minister has not been truthful to the media, to his own advisers and Number 10 officials, and to the party in disclosing what he knew."
Mr Skidmore, who serves as universities minister until 2020 added: "This is an extremely grave situation, that is tantamount to an effective cover-up of sexual abuse that would never be tolerated in any normal, functioning, workplace."
He argued that because the new facts had only come to let after the previous vote of no-confidence, which Mr Johnson survived, the rules needed to be changed to allow another to take place.
It was "highly unlikely that the party would have confidence in someone who has acted in this manner", the ex minister claimed. He added that he had lost confidence in Mr Johnson’s ability to lead the party.
Under the existing rules the prime minister cannot face another vote for a year, but the party's 1922 committee can change the rules.
The prime minister has been hit by a slew of senior resignations including chancellor Rishi Sunak and health secretary Sajid Javid.
Mr Sunak said said the public expected "government to be conducted properly, competently and seriously" as he quit over the Chris Pincher affair.
And in an incendiary letter, Mr Javid said the British people "expect integrity from their government" but now believed Mr Johnson was neither competent nor "acting in the national interest".
Other MPs to quit government roles so far include Andrew Murrison, Jonathan Gullis and Saqib Bhatti.
Mr Johnson's premiership has been rocked by scandal after scandal since the autumn, including the Partygate revelations.
But it was the prime minister's handling of allegations that his deputy chief whip had groped someone in a private members' club that has put his leadership in the latest danger.
Mr Johnson was accused of lying about what he knew about Chris Pincher's record of allegations before he appointed the Tamworth MP to the senior governemnt role.
The prime minister's authority had already been damaged by a confidence vote which saw 41 per cent of his MPs vote against him – but he did not quit.
Mr Pincher has quit his government job and lost the Conservative whip in parliament; he says he embarrassed himself by his behaviour and attributed it to drinking too much.
