The Conservative whip has been suspended from Chris Pincher after an investigation was launched into allegations he drunkenly groped two men at a private members’ club.

Boris Johnson bowed to pressure after a complaint about the MP was made to Parliament’s watchdog that examines allegations of bullying, harassment or sexual misconduct.

Mr Pincher dramatically quit as Tory deputy chief whip after a drunken incident in which he allegedly groped two guests at the exclusive London club.

The Prime Minister had been resisting calls to go further and remove the whip, meaning the MP for Tamworth in Staffordshire would sit as an independent in the Commons.

In the absence of any formal complaints, it was not appropriate to stop an appointment on the basis of unsubstantiated allegations

But on Friday, the action was taken after a formal complaint was made to the Independent Complaints and Grievance Scheme (ICGS).

A spokeswoman for Conservative chief whip Chris Heaton-Harris said: “Having heard that a formal complaint has been made to the ICGS, the PM has agreed with the chief whip that the whip should be suspended from Chris Pincher while the investigation is ongoing.

“We will not pre-judge that investigation. We urge colleagues and the media to respect that process.”

Mr Johnson spoke to several individuals on Friday, including a Tory MP who was with one of the men who was allegedly groped by Mr Pincher, a Downing Street source said.

“The account given was sufficiently disturbing to make the PM feel more troubled by all this,” the source told the PA news agency.

The Prime Minister was said to have been waiting for a formal investigation to begin before suspending the whip, as opposition parties said Mr Pincher’s position as an MP was untenable.

Downing Street appeared to acknowledge that there had been concerns when he was appointed to the key post of deputy chief whip, with responsibility for discipline over Tory MPs, in February.

However a No 10 spokesman said the Prime Minister had not been made aware of anything that would have prevented the appointment going ahead.

“In the absence of any formal complaints, it was not appropriate to stop an appointment on the basis of unsubstantiated allegations,” the spokesman said.

Downing Street appointed former housing minister Kelly Tolhurst, the MP Rochester and Strood, to be the next deputy chief whip.

The only two women Tory MPs to chair Commons select committees, Caroline Nokes and Karen Bradley, had earlier called for a policy of “zero tolerance” for any such alleged conduct, with any MP facing such allegations having the Conservative whip withdrawn while they are investigated.

In a joint letter to the Prime Minister, they said: “The party and, by extension, the Government are at risk of serious reputational damage by the current approach.

“We urge you to act swiftly to introduce a code of conduct for all Conservative members of Parliament which is clear in terms of the expectations of behaviour and which can be applied in a fair, independent manner so as to avoid any suspicion of bias.”

Downing Street confirmed there had been an exchange of messages between Mr Johnson and Mr Pincher on Thursday evening but declined to say whether it was before or after Mr Pincher submitted his resignation.

A No 10 spokesman said: “The Prime Minister thinks it was right for him to have resigned and he has accepted his resignation.

“He believes that the behaviour was unacceptable, which is why he’s accepted the resignation.”

Mr Johnson was under pressure to explain why he gave Mr Pincher such a sensitive post amid reports that he had been advised not to do so.

The Tamworth MP was brought in alongside chief whip Chris Heaton-Harris, another trusted ally, to shore up support for the Prime Minister amid growing unrest among Tory MPs over the disclosures about lockdown parties in Downing Street.

In 2017 Mr Pincher quit the whips office after a complaint over an unwanted pass at the former Olympic rower and Conservative candidate Alex Story.

However he was reinstated two months later as a senior whip by Theresa May after having referred himself to both the police and the Conservative Party complaints procedure.

Asked whether Mr Johnson had been warned about his latest appointment, following spells at the Foreign Office and the Ministry of Housing, the No 10 spokesman said: “He was not aware of any specific allegations.”

The latest disclosures come after the Conservative Party has been hit by a series of scandals relating to sexual misconduct.

In May, Neil Parish quit as MP for Tiverton and Honiton after admitting viewing pornography in the Commons chamber, while the previous month Wakefield MP Imran Ahmad Khan was jailed for 18 months for sexually assaulting a 15-year-old boy.

In both cases the Conservatives lost the ensuing by elections.

A third unnamed Conservative MP has been told by the whips to stay away from Parliament after he was arrested on suspicion of rape and other offences.

Deputy Labour leader Angela Rayner said: “Boris Johnson has been dragged kicking and screaming into taking any action at all. He just can’t be trusted to do the right thing.

“This whole scandal is yet more evidence of his appalling judgment.”

In his resignation letter to the Prime Minister, Mr Pincher apologised for his behaviour, saying it had been “the honour of my life” to have served in the Government.

“Last night I drank far too much. I’ve embarrassed myself and other people which is the last thing I want to do and for that I apologise to you and to those concerned,” he said.

The alleged incident reportedly took place in the Carlton Club, the original home of the Conservative Party, in London’s Piccadilly.

Scotland Yard said it had not received any reports of an incident at the club.

The Commons said the ICGS “operates on the basis of confidentiality for the benefit of all parties”, adding: “Therefore, we cannot provide any information on any complaint, including whether or not a complaint has been received.”