A senator from Australia's main opposition Liberal Party facing accusations of sexual misconduct by several female politicians has resigned from the party but will stay in parliament, the senator's office said on Sunday.

The claims against Senator David Van follow a 2021 inquiry into Australia's parliament house culture that found one in three people working there had experienced sexual harassment.

Van, who denies the accusations, said in a message to the president of the Victorian division of the Liberal Party that he would resign his membership immediately.

"I cannot remain a member of a party that tramples upon the very premise on which our justice system is predicated," Van said in the correspondence seen by Reuters and confirmed by a spokesperson for the senator.

Van would remain in parliament as an independent senator, the spokesperson said.

Liberal Party leader Peter Dutton on Friday asked Van to resign after independent Senator Lidia Thorpe, using parliamentary privilege, said she was sexually assaulted in the previous parliamentary term, a claim Van immediately denied.

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 claim has also emerged against senator Van, Dutton told the media on Friday, without giving details. (Reuters)