Welsh Secretary Alun Cairns quits amid accusations he lied about aide in row over rape trial
Mr Cairns denied knowing Ross England made claims about a victim's sexual history that caused the trial to be abandoned 2018 until the story broke October 2019.
But a leaked email revealed he knew about the allegation in August 2018 - four months before he backed Mr England to be a Tory candidate for the Welsh Assembly.
In his resignation letter to the PM, Cairns said "You will be aware of allegations relating to the actions of a party employee and candidate for the Welsh assembly elections in the Vale of Glamorgan. This is a very sensitive matter, and in light of continued speculation, I write to tender my resignation as secretary of state for Wales." he added "I will co-operate in full with the investigation under the Ministerial Code which will now take place and I am confident I will be cleared of any breach or wrong doing."
The announcement is a massive blow to Boris Johnson, and came less than an hour before he was due to launch his election campaign on the steps of Downing Street.
Johnson vowed to lead Britain out of its "rut" and stop Britain's Remainer MPs from blocking Brexit. It was also expected he would bang the drum for his big spending plans to boost investment in hospitals, schools and the police.
Jeremy Corbyn had called on the ex-Welsh Secretary to stand down as parliamentary candidate in the Vale of Glamorgan. Corbyn said "Obviously, legally he can stand as a candidate but does he have a moral right to stand as a candidate? If he's stepping down as a minister because of his involvement then I would have thought the very least the Conservative Party can do is not put him up as a candidate in the next election."
Labour's candidate for the seat was Belina Loveluck-Edwards.
Christina Rees, shadow welsh secretary, accused Cairns of "brazenly lying" and also called on him to quit.
The Cabinet minister claimed he was unaware of former staff member Ross England's role in the collapsed trial until the story emerged.
Outcome:
Alun Cairns resigned after he was accused of "brazenly lying" about when he found out his former aide had "sabotaged" a rape trial.