SYDNEY Australia's main opposition Liberal Party leader asked a senator to resign on Friday following allegations of sexual misconduct against him by female senators, which he has denied.

The accusations against Liberal Party Senator David Van follow numerous previous complaints about the culture in Australia's parliament house, which led to an inquiry in 2021 that found one in three people working there had experienced sexual harassment.

Independent senator Lidia Thorpe on Thursday accused Van of sexual assaulting her during the previous parliamentary term - which Van denied and Thorpe later withdrew to comply with Senate rules preventing comments on someone's character.

Following Thorpe's comments, former Liberal senator Amanda Stoker said in a statement that Van inappropriately touched her at a party in 2020 by squeezing her bottom twice.

A third allegation has also emerged against senator Van, opposition Liberal Party leader Peter Dutton told the media on Friday, without giving details.

"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," Dutton told Nine Radio.

Dutton said his decision was not a reflection on Van's guilt or innocence, and he had referred the matter to the parliament's workplace authority for investigation.

Van said he was "utterly shattered" and "stunned that my good reputation can be so wantonly savaged."

"I will fully co-operate with whatever process Mr Dutton proposes to determine these matters as quickly and fairly as possible," he said in a statement.

A high-profile case of a former government adviser accused of sexually assaulting a colleague in parliament rocked the Liberal-led government of then Prime Minister Scott Morrison, who struggled to placate public anger before a general election amid reports of sexual abuse, discrimination and misconduct in parliament. Morrison lost the election in May last year.

(Reporting by Praveen Menon; Editing by Stephen Coates)