NSW Deputy Premier John Barilaro says his Nationals colleague Michael Johnsen must immediately resign from parliament amid new allegations of 'disgusting' behaviour.
Premier Gladys Berejiklian agrees, saying the allegations against the Upper Hunter MP were unacceptable.
The ABC on Tuesday reported Mr Johnsen offered a sex worker $1000 to have sex with him in parliament and sent the woman lewd text messages and an obscene video while sitting in the parliamentary chamber.
The report comes a week after the Nationals MP went on leave and moved to the crossbench, having denied allegations - first aired in parliament - that he raped the same woman at a Blue Mountains lookout in 2019.
NSW Police are investigating but are yet to press charges.
Mr Barilaro said in a statement on Tuesday that Mr Johnsen must resign immediately and his role as an MP was "untenable".
"This is disgusting behaviour and will never be acceptable, nor should it be, and I'm calling for Mr Johnsen to resign from parliament immediately," he said.
The woman told the ABC she exchanged hundreds of messages with Mr Johnsen after responding to his online advertisement for sex in August 2019, including lewd messages which he allegedly sent during parliamentary question time.
Ms Berejiklian told reporters she was disgusted by the reported behaviour and supported calls for Mr Johnsen to resign from parliament.
"I know the challenges that are there for women, I've experienced them myself, and this goes to the heart of cultural change that's required, not just in government and politics but in every sphere of society," she said.
"If people think it's okay to engage in that type of behaviour in the workplace, a workplace which establishes our laws ... it's completely unacceptable."
The new allegations against Mr Johnsen are the latest engulfing the Liberal Party, particularly in federal parliament, since ex-staffer Brittany Higgins said she was raped in a government minister's office in March 2019.
Ms Berejiklian last month appointed ex-NSW MP Pru Goward to "stress test" all NSW parliamentary processes on harassment or sexual assault.
The premier also said she supported gender quotas for parliamentary candidates but said it wouldn't be a silver bullet for change.
"You can have the best rules in the world, you can have the best number of things in place ... but at the end of the day it comes down to respect and equality, and how people treat each other.
"Often I think to myself when I'm in certain situations ... would that have happened or been said if I was a different gender?"
Education Minister Sarah Mitchell - a Nationals MP - said it was "appropriate" that Mr Johnsen didn't sit in the partyroom, and he should resign.
But Opposition Leader Jodi McKay told reporters that Ms Berejiklian had not done enough to uphold standards among MPs.
"Michael Johnsen has to resign - today," Ms McKay said.
"This is politics in NSW under Gladys Berejiklian ... this is not about women, it's actually about the behaviour of her MPs time and time again.
"This doesn't get any worse ... when you're in the chamber during a water debate in a drought and you're texting about how horny you are."