Opposition Leader Peter Dutton wants embattled senator David Van to quit parliament, after revealing a third woman has accused the Victorian Liberal of improper behaviour.

Mr Dutton’s statement came as Senator Van hit back, declaring his “good reputation has been wantonly savaged” by complaints about his conduct that have emerged this week.

Mr Dutton expelled Senator Van from the Liberal party room on Thursday after independent Senator Lidia Thorpe first accused him of harassment and assault, and then former Liberal senator Amanda Stoker said he had groped her.

Asked on Friday if he was aware of further allegations against the now-crossbench senator, Mr Dutton replied: “Yes.”

“I raised another allegation with Senator Van, but I’m not going to comment in relation to those matters otherwise,” he told Nine’s Today program.

“I made a decision yesterday based on all of the information that was available to me … that’s a decision I don’t regret at all.

“I believe it is in the best interests of the Liberal Party and that’s what I have acted upon and I don’t want Senator Van sitting in our party room. I have made that clear.”

Mr Dutton said the alleged behaviour was unacceptable.

“The thought of sexual assault against any woman in the workplace is not something that I would tolerate,” he said.

“It’s been an issue in the press gallery, been an issue in Parliament House and obviously … I’ve referred the matters to that independent workplace authority for investigation.”

Mr Dutton said his decision did not reflect whether the women’s claims were true or not. But he told Nine radio later that he had spoken to the Victorian branch of the Liberal party about whether Senator Van should remain in parliament.

“The membership of the party is an issue for the party to resolve [but] I think it’s in everyone’s best interest that he resign from the parliament, and I hope he is able to do that sooner than later,” Mr Dutton said.

Also on Friday, however, Senator Van hit back at the escalating accusations, saying he looked forward to clearing his name.

“I am utterly shattered by the events of the past days and stunned that my good reputation can be so wantonly savaged without due process or accountability,” he said in a statement.

“I will fully cooperate with whatever process Mr Dutton proposes to determine these matters as quickly and fairly as possible.”

“While I understand the public interest is high, I will not be making any more public statements on the allegations until a proper examination of these claims is concluded.”

The storm surrounding Senator Van erupted this week when Senator Thorpe used parliamentary privilege, to accuse him of harassment and sexual assault, allegations he strongly denied.

Senator Thorpe later withdrew the comments, to comply with Senate rules. But she followed up on Thursday with a more detailed claim of assault and harassment at parliament, while naming no names.

Later on Thursday, Ms Stoker accused Senator Van of inappropriately touching her at a 2020 event.

“He did so by squeezing my bottom twice,” she said, adding that the groping was not accidental and was “unprofessional and uninvited”.

Senator Van has said he has no recollection of the incident and he would never have acted inappropriately towards his then-colleague.

On Friday, Senator Thorpe said the fallout from her bombshell accusations had been horrible and parliament was not a safe workplace for women.

“It’s such a toxic culture … I’ve never experienced such a toxic workplace culture towards women,” she told ABC Radio.

“I had a media pile-on that day and it wasn’t until a white woman stood up and said ‘yeah, this happened to me too’ that the media took notice.”

The former Greens senator said the case exemplified why women did not speak out against improper behaviour.

“I was not believed, I was questioned, I was absolutely demonised that day, by everybody,” she said.

This week’s accusations have reignited debate over parliament’s culture. On Friday, Liberal MP Bridget Archer said the issues had been highly politicised.

“If you’re observing the behaviour and commentary that’s been going on in parliament in the last couple of weeks, and the commentary in the media … you would be disinclined to come forward and say that you had experienced sexual assault,” she told ABC Radio.

“Because it’s really as Senator Thorpe said – it’s really toxic.”

Independent MP Helen Haines said it was appropriate for Mr Dutton to stand Senator Van aside from the Liberal party room.

“If one woman doesn’t feel safe in our parliament, then no woman [does],” she said.

But the Victorian MP said there was still “quite a way to go” following the landmark review of parliamentary culture by former sex discrimination commissioner Kate Jenkins.

Liberal deputy leader Sussan Ley said the new Parliamentary Workplace Support Service was doing outstanding work, but there was room for improvement.

“It is always difficult to step up and talk about things that have happened and workplaces do have to improve,” she told Seven’s Sunrise program.

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-with AAP