The controversial Presidents Club gala has claimed its first political victim, after Lord Mendelsohn was effectively sacked from the Labour's frontbench.

The 51-yea-old peer was asked to step down by party leader Jeremy Corbyn after it emerged Mendelsohn had attended the men-only event at the Dorchester Hotel in London, where female hostesses were allegedly subjected to sexual harassment.

The scandal broke on Wednesday (24 January) with revelations from an undercover investigation by FT journalists.

The club, which has raised millions of pounds for charity over its 30-year existence, folded in the face of claims that many of the men at its gala dinner last week harassed, groped and propositioned female hostesses.

The hostesses, who were paid £150 for the night, had to sign non-disclosure agreements and were made to wear short skirts and black underwear, they told the FT.

Comedian David Walliams hosted the event, where £2m was raised for charity through auction items such as lunch with Foreign Secretary Boris Johnson and tea with Bank of England governor Mark Carney.

Mendelsohn's wife, Nicola, is Facebook's vice-president for Europe, the Middle East and Africa and has previously spoken in favour of women's rights. While there is no indication that the Labour peer was one the attendees who engaged in lewd behaviour, Corbyn said there could be no excuse for those who had attended what he described as an "appalling event".

"Jeremy Corbyn has asked Lord Mendelsohn to step back from the front bench [. . .] and he has agreed to do so," a Labour spokesman was quoted as saying by The Times.

"Lord Mendelsohn has previously made clear that he attended part of the dinner as president of a charity that received support from the event and he had no knowledge of an after-party. Lord Mendelsohn did not witness any of the appalling incidents described in reports and has unreservedly condemned such behaviour."

Mendelsohn's decision to step aside will crank up the pressure on Nadhim Zahawi, the children and families minister, who also attended the event.

The Conservative MP took to Twitter to defend himself once details of the FT expose began to emerge.

"I do unequivocally condemn this behaviour," he tweeted. "The report is truly shocking. I will never attend a men-only function ever."

He later revealed that he told Downing Street that he and some friends arrived at the dinner at 8pm and left at 9.35pm as he "felt uncomfortable".

On Thursday, Zahavi was summoned up to appear in front of Julian Smith, the Tory party's chief whip, where he was given a "dressing down" and asked to provide further details of his appearance at the event.

"I understand that Nadhim Zahawi left early from that particular event but, when I read the report of that event that took place, frankly, I was appalled," Theresa May told the BBC.

"I thought that that sort of approach to women, that objectification of women, was something that we were leaving behind."

Meanwhile, the Presidents Club trustee, David Meller, was forced to resign from his roles at the Mayor's Fund for London and the Department for Education.

In the aftermath of the scandal, charities which had received donations from the event said that they would give back the money. Among them was Great Ormond Street Hospital Children's Charity which was just one of several charities that had benefited from the £20m raised at the annual dinners.