NSW Premier Gladys Berejiklian says she’s concerned and distressed by sexual assault allegations levelled against sidelined frontbencher Gareth Ward,  but has stopped short of calling for his resignation.

But Mr Ward insists he’s done nothing wrong and is yet to be contacted by police over the allegations, which he says he learned about in media reports.

The Kiama MP on Thursday night stepped aside as families, communities and disability services minister after identifying himself as the politician under investigation for “sexual violence-related offences” dating back eight years.

Police are investigating the allegations, which reportedly took place from 2013.

Mr Ward said in a statement on Thursday evening that he would also recuse himself from the Liberal Party room and move to the crossbench.

The incident could push the Berejiklian government up to three seats in minority, depending upon the outcome of the May 22 Upper Hunter by-election.

Former Upper Hunter Nationals MP Michael Johnsen resigned in March over allegations he raped a sex worker in 2019, which he denies.

Scandal-plagued Drummoyne MP John Sidoti also remains on the crossbench.

Ms Berejiklian on Friday said that Mr Ward had expressed his shock and said he knew little of the allegations levelled against him.

But she supported Mr Ward’s decision to move to the crossbench for now and was not seeking his resignation from Parliament at this stage because he had not yet been contacted by police and was not aware of the details of the allegations.

“I feel under the circumstances, given there was speculation, even though he’s not been contacted by police, I think he’s done absolutely the right thing in stepping aside in the party room,” she said.

“After the reports came out I spoke to him and asked him whether he’d done anything wrong. He denied any wrongdoing. I asked him if police had contacted him and he said no.”

Ms Berejiklian said “all of Parliament” was “quite shocked” yesterday when they heard what Mr Ward was being investigated over.

“What transpired yesterday afternoon was extremely concerning and distressing,” she said.

“He was very categorical in saying police hadn’t contacted him,” she said.

Deputy Premier John Barilaro said it was “Groundhog Day” for the Coalition, coming two months after Mr Johnsen’s resignation.

The allegations against Mr Ward also come as sexual harassment and bullying policies for NSW government ministers’ offices face an overhaul, with a “brutal” review deeming current rules ineffective and unclear.

-with AAP