RISHI Sunak has claimed he didn't know about any specific concerns relating to the conduct of disgraced MP Gavin Williamson despite his ex-party chairman claiming otherwise.

Williamson resigned as a minister on Tuesday as allegations of bullying mounted against him.

No 10 is probing claims Williamson told a senior civil servant to “slit your throat”, while the Tory party and Parliament’s bullying watchdog are looking into allegations made by former chief whip Wendy Morton.

During Wednesday's Prime Minister's Questions, Sunak insisted he was not made aware of Williamson's behaviour before appointing him into the Cabinet as he faced a grilling from the opposition.

But the account would appear to not add up as Jake Berry, who was Tory party chairman under Liz Truss, has claimed he told Sunak about a complaint just 24 hours before he was handed a job in the government.

Boris Johnson fired Williamson – a close ally whom he later gave a controversial knighthood – as education secretary after the exams scandal during the pandemic, and Theresa May sacked him as defence secretary over a leak from the National Security Council.

READ MORE: Tories 'to lose Douglas Ross's Moray seat' in UK constituency shake-up

Pressure had been mounting on Sunak to sack him after fresh allegations emerged about his “unethical and immoral” behaviour.

As the PM arrived to face the music in the Commons, Labour leader Keir Starmer demanded answers from Sunak and asked if he regretted making Williamson a minister.

The National: Gavin Williamson resigned as Cabinet Office minister on TuesdayGavin Williamson resigned as Cabinet Office minister on Tuesday (Image: PA)

Sunak said: "The behaviour complained of was unacceptable and it is absolutely right that the right honourable gentleman has resigned.

"I did not know about any of the specific concerns relating to his conduct as secretary of state and chief whip which date back some years.

"I believe people in public life should treat people with consideration and respect and these are the principles this government will stand by."

Williamson allegedly lashed out at Morton last month amid unfounded claims she excluded him from attending the Queen's funeral.

Morton told the party on October 24, the day before she resigned as chief whip, that she wished to make a formal complaint and separately alerted the Cabinet Office propriety and ethics team.

READ MORE: UK could bypass Scottish Parliament in devolved areas, MSPs warn

Berry issued a statement saying that he had told the PM and his incoming chief of staff the same day - 24 hours before Sunak entered No 10 - that Morton was submitting a complaint about the messages.

Sunak added in the Commons: "I obviously regret appointing someone who has had to resign in these circumstances, but I think what the British people would like to know is that when situations like this arise, they will be dealt with properly.

"That's why it is right he resigned and it is right there is an investigation to look into these matters properly."