Conservative MP Fred Nile says he wants topless bathing banned in NSW to protect Sydney's Muslim and Asian communities.

The Reverend Nile has rejected allegations that prudishness is behind a bill he has prepared to ban nudity, including topless sunbathing, on the state's most popular beaches.

Australia's reputation as a conservative but culturally inclusive sociery was at risk of erosion by more liberal overseas visitors, he said.

"Our beaches should be a place where no one is offended, whether it's their religious or cultural views," he said.

"If they've come from a Middle Eastern or Asian country where women never go topless - in fact they usually wear a lot of clothing - I think it's important to respect all the different cultures that make up Australia."

The practice was at risk of raising the ire of Muslim men in particular, Mr Nile said.

"I don't want to have any provocations or disturbances on our public beaches," he said.

Acting Premier Carmel Tebbutt and the NSW Opposition Leader, Barry O'Farrell, have both said that topless bathing is an issue for local councils, not state governments.

But Mr Nile said he believed most politicians would come around once all the issues were considered.

"I think if you survey Australian women you'll find a lot of women would be uncomfortable if it became the custom [to be] topless at the beach," he said.

"Australia's always been a conservative country as far as beachwear goes.

"Once being topless is accepted as lawful the next question will be why can't women go totally nude on a public beach and I don't think Australians want to go down that pathway."

NSW Liberal powerbroker David Clarke and Labor MP Paul Gibson have reportedly vowed to support the bill.

AAP reports:

Mr O'Farrell said topless bathing was not a matter for Parliament.

"This is a matter for local councils to deliberate, at a time when state parliament should be focusing on roads, public transport, hospitals and education," he said today.

"It doesn't rate on the list of important matters for the Parliament of NSW."

Up to individuals: Gillard

Speaking to reporters in Melbourne, acting Prime Minister Julia Gillard said the topless issue was one of context and clear signage.

"People want to go to the beach and use the beach in a variety of ways. Obviously family groups want to go to the beach, people who want to get a bit of sun all over also want to go to the beach," she said.

"As long as people know what the rules are and know what to expect I think it is a matter for the individuals involved."

Ms Gillard urged topless bathers to be sun smart.

"There is also a stage where people should be getting the hat on, getting the shirt on and getting the sunscreen on," she said.

Topless bathing not an issue: Bondi mayor

Waverley Council Mayor Sally Betts says she is aghast at moves by state politicians to outlaw women from sunbathing topless on NSW beaches.

"We've got alcohol-related violence, we've got under-age drinking and anti-social behaviour in the public domain - those are really important issues," Ms Betts told Fairfax Radio Network.

"If the Reverend Nile really wants to help people he should focus on those issues."

Ms Betts said she was at the beach on Christmas Day and Boxing Day and did not notice any topless women.

But if it was a problem, she would have heard about it, she said.

"In Waverley, we have a very involved community. They complain about everything," she said.

"But nobody has complained to me about topless [women]."