Rishi Sunak was braced for another possible by-election after former Government whip Chris Pincher was recommended for an eight-week suspension for drunkenly groping two men.

The Standards Committee said in its report on Thursday that the MP’s conduct last summer was “profoundly damaging” and “especially grave” because it amounted to an abuse of power.

The committee upheld allegations Mr Pincher “groped” two men at London’s exclusive Carlton Club while he was the Conservative deputy chief whip, in a scandal that hastened Boris Johnson’s downfall.

The MP for Tamworth’s actions in June last year were described as “unwanted, inappropriate and upsetting”, in what amounted to an “egregious case of sexual misconduct”.

One of the men told the investigation that “the incident has significantly impacted me”, adding: “I have become increasingly anxious as a result of the incident.”

The committee said: “Mr Pincher’s conduct was completely inappropriate, profoundly damaging to the individuals concerned, and represented an abuse of power.”

It concluded that he broke the MPs’ code of conduct by behaving in a way that would cause “significant damage to the reputation and integrity” of the Commons.

The eight-week suspension is one of the longest ever recommended and greatly exceeds the 10-day threshold that could trigger a recall petition in his Staffordshire seat.

Voters could expel him if the wider Commons first approves the report from the committee comprised of MPs of different parties and lay members.

The complainant, a House of Lords employee at the time, told the investigation that at around midnight on June 30 last year Mr Pincher grabbed his forearm in the bar of the private members club “for longer than necessary”.

He said the MP went on to “stroke the back of my neck” before he squeezed his backside.

“I was so shocked at what had just happened,” the complainant said.

“I found the incidents with Mr Pincher to be traumatic and the incidents continue to significantly affect my sleep whenever I have to recount Mr Pincher’s behaviour.”

A civil servant who was a witness in the investigation said Mr Pincher touched his bottom before squeezing his testicles for several seconds.

He said: “The incident with Mr Pincher has significantly impacted me. I have become increasingly anxious as a result of the incident, and I am now taking medication to manage my anxiety.

“I am also fearful about whether this incident will impact my job and future career plans. After the incident, I stopped exercising, which has resulted in my gaining a lot of weight.”

Mr Pincher denied breaching the code of conduct, but told the investigation he was “very sorry” for his actions, which he is unable to recall.

He admits he was “heavily intoxicated” but has expressed “genuine contrition” and taken responsibility for his actions, the committee said.

Deputy Labour leader Angela Rayner called on Mr Pincher to “do the decent thing and resign” as an MP.

“Chris Pincher’s actions are shocking. But what’s even worse is the way the Conservative Party protected him – even promoting him despite a previous investigation into his conduct,” she said.

In a statement, Mr Pincher said he apologises “sincerely” and will not fight to remain as Tamworth’s MP.

“I resigned as deputy chief whip and have already said that I will not seek re-election,” he said.

“I have sought professional medical help, which is ongoing and has been beneficial to me, for which I am grateful.”

The Liberal Democrats urged the Prime Minister to “show some backbone” by voting to suspend Mr Pincher when the report goes before the Commons.

The Prime Minister’s official spokesman said it was for Mr Pincher to decide whether he should quit Parliament.

Mr Sunak’s spokesman, asked whether Mr Pincher should resign, said: “The report raises serious issues. It is really a question for the MP.

“He is not a member of Government, so it is not one for me.”

The official added that he could not say whether the Prime Minister would participate in any Commons vote on the sanction recommended.

Mr Pincher resigned as a Government whip after the incident and subsequently lost the Tory whip, meaning he now sits in the Commons as an independent.

Already battling to remain prime minister while dogged by partygate allegations, Mr Johnson’s handling of the Pincher affair was the final straw for his Cabinet support.

He had appointed the MP to the senior role overseeing party discipline despite being aware of an official complaint about Mr Pincher’s behaviour.

If 10% of Tamworth voters sign the possible recall petition, then the Conservatives, reeling in the national polls, will have to defend another constituency they won in 2019.

Two of three by-elections due on July 20 were triggered by the resignations of Mr Johnson and his ally Nigel Adams.

The third was prompted by the resignation of David Warburton amid allegations of sexual harassment and cocaine use.

Mr Pincher has been comfortably voted for by Tamworth since 2010, and he won a 19,634 vote majority at the last general election.