Senator Seselja backed a Senate motion from former One Nation senator and new Katter's Australia Party recruit Fraser Anning denouncing the NSW parliament for the legislation and saying it restricted free speech.

The motion split Liberal party senators but gained support from social conservatives inside the Coalition before it was defeated with overwhelming opposition from Labor, including new ACT senator David Smith, the Greens and other crossbenchers.

Seventeen senators - including 14 from the Coalition - voted on Monday supporting the motion that said NSW had copied the "socialist" Victorian government in banning anti-abortion protests outside clinics.

"These 'exclusion zones' are nothing more than an attempt to restrict freedom of speech," it said.

"No such 'exclusion zones' apply to any other forms of protest and violent left-wing protesters opposed to democracy and capitalism do not face such draconian punishments.

"A democratic government should not involve itself in regulating the faith and prayers of Australians, much less imprisoning them."

The laws, which provide a 150-metre exclusion zone around clinics and make it an offence to film staff and patients without their consent, passed NSW parliament in June receiving the backing of premier Gladys Berejiklian, state Nationals leader and Monaro MP John Barilaro, and other Coalition party members.

Senator Seselja did not comment directly to Fairfax Media about his vote but a spokeswoman said his views on exclusion zones were "well-canvassed".

"He voted consistently with those views along with an overwhelming majority of those Coalition senators who participated in the vote yesterday," she said.

Liberal senators Richard Colbeck and Simon Birmingham opposed the motion.

Labor MP for Fenner Andrew Leigh defended laws establishing exclusion zones in NSW, Victoria, Tasmania, the Northern Territory and the ACT, saying they responded to a history of women being harassed by anti-abortion protesters as they entered abortion clinics.

"No woman makes the decision to terminate a baby lightly. It is a decision best made in consultation with a medical practitioner and one which involves significant stress," he said.

Senator Seselja has previously criticised powers letting ACT police officers ban and fine anti-abortion protesters outside a clinic in Canberra as incompatible with freedom of speech and religion, and has urged changed.

"I think provided that [protest] is done peacefully and in a way that is not violent or in any other way infringing on the rights of other people, then I think they should be free to pray, to speak, and to protest peacefully. I don't think that law supports those principles," he said.

The legislation was introduced by the Greens in 2015, who argued protesters were causing distress and making patients walk through "a wall of people who were making judgments".

ACT laws make it illegal to harass, intimidate, obstruct, photograph, or film women as they access Canberra's abortion clinic.

Pro-life supporters had gathered outside the clinic for 17 years but are now banned from demonstrating within 50 metres of the site.