Many of the biggest names in British business quit the CBI on Friday after a second allegation of rape threatened the survival of the employers’ organisation.

Groups ranging from insurer Aviva and car manufacturers Jaguar Land Rover and BMW to payments company Mastercard and retailer John Lewis said they were cancelling their memberships after the allegations published by the Guardian.

The world’s biggest ad group WPP, broadband and mobile company Virgin Media O2, the Big Four accounting firm EY, and ITV, the broadcaster, also all cut ties.

The newspaper reported that a woman alleged she was raped while working for the CBI — the second to make an accusation of rape involving the organisation.

“In light of the very serious allegations made, and the CBI’s handling of the process and response, we believe the CBI is no longer able to fulfil its core function — to be a representative voice of business in the UK,” Aviva said. “We have therefore regrettably terminated our membership with immediate effect.”

The Association of British Insurers, the trade body for the UK insurance industry, said it was leaving “with immediate effect”, while Lloyd’s of London also confirmed it would not be renewing its membership.

The new rape allegation, which the CBI has now passed to the police, is the latest in a series of claims about the workplace culture, including sexual harassment, drug-taking and bullying that have rocked the UK employers’ organisation in recent weeks.

Ann Francke, chief executive of the Chartered Management Institute, a professional body that encourages better management practices, said the CBI was now facing an “absolutely existential crisis” due to the pattern of allegations and leadership failures.

Vitality, a smaller UK health insurer, also quit, as did Suffolk-based brewer Adnams and chip intellectual property designer Imagination Technologies.

One person close to Imagination Technologies said the recent allegations “tipped the balance” in favour of quitting, but the original driver had been a lack of value for money.

In further blows, Asda, Lidl, Reckitt Benckiser and Diageo said they had paused engagements with the CBI, while Shell and Ford had already previously suspended their activities with the group, according to people familiar with the matter.

Barclays, HSBC, NatWest, Lloyds Banking Group, TSB, JPMorgan, Morgan Stanley, Macquarie Group and the Bank of Ireland have all also paused activities with the CBI pending the outcome of the investigation.

The Guardian reported the new case of rape had taken place at one of the CBI’s overseas offices, but declined to specify the date of the incident or the country where it took place in order to protect the alleged victim’s identity.

The CBI said on Thursday that it had been passed information about a serious crime and was now “liaising closely” with the police.

The City of London Police is already investigating an allegation of rape at a 2019 CBI staff party on a boat on the river Thames, alongside a series of other allegations of misconduct made by a dozen people who have worked at the organisation.

Fox Williams, the law firm, is conducting an independent investigation into those allegations at the request of the CBI, which has led to the suspension of three staff. The CBI has said it expects to publish the conclusions from the inquiry early next week.

Separately, the CBI sacked its former director-general Tony Danker this month for previous workplace misconduct. Danker said this week that he had been made the “fall guy” for the much more serious allegations.

The Guardian report included graphic details of the second alleged rape, which the woman said took place at the hands of two men after a night of heavy drinking.

The woman said she had no recollection of the rape itself, but had described in detail the physical signs that led her to believe she was raped and was later presented in the office with an explicit photograph related to the incident.

The woman told the Guardian that she blamed the CBI for allowing an atmosphere to be created in which such incidents could take place, and for failing to provide adequate human resources support.

CBI president Brian McBride said the allegations reported in the Guardian were “abhorrent” and that the CBI had not been previously aware of them. “It is vital that they are thoroughly investigated now and we are liaising closely with the police to help ensure any perpetrators are brought to justice,” he added.

The Guardian also reported a 2018 case in which a female employee was stalked by a male colleague. An internal CBI investigation made a finding of harassment, but the incident was not taken to the police.

Dame Carolyn Fairbairn, who was director-general of the CBI at the time, told the Guardian she was not made aware of the complaint, describing the decision not to bring it to her attention as “appalling”.

Additional reporting by Judith Evans, David Sheppard, Laura Onita, Owen Walker, Anna Gross and Oliver Barnes