Prime Minister Malcolm Turnbull has dismissed a conservative-backed same-sex marriage bill, warning sweeping religious protections that discriminate against gay couples will have no chance of passing Parliament.
Mr Turnbull was responding to Liberal senator James Paterson's bill, which would extend religious protections to allow private businesses to refuse goods and services for gay weddings if they have "conscientious objections".
On the eve of the same-sex marriage survey result, Mr Turnbull said MPs and Senators would be free to move amendments to any bill to change the Marriage Act, but those contained in Senator Paterson's plan would have "virtually no prospect of getting through the Parliament".
"Assuming there is a Yes vote tomorrow — the pollsters will really be rocked if there isn't — but assuming there is, there will be a Private Members Bill and amendments can be moved and if people want to move an amendment of that kind, well, you know, they can," he said.
"[But] I don't believe Australians would welcome, and certainly the Government would not countenance, making legal discrimination that is unlawful today."
Backed by his conservative colleagues, Senator Paterson released a Private Members Bill on Monday that he argues contains greater religious protections than the one put forward months ago by Liberal colleague Dean Smith.
The move has inflamed tensions between the conservatives and moderates in the party and set the stage for a lengthy parliamentary debate over religious freedoms and anti-discrimination laws.
Anticipating the Yes campaign will prevail, Senator Smith has placed his bill on the notice paper, which, crucially, has been co-signed by Liberals Linda Reynolds and Jane Hume, Labor's Penny Wong and Louise Pratt, Greens leader Richard Di Natale and Skye Kakoschke-Moore from the Nick Xenophon Team.
Senator Reynolds said that while she backed the bill, she reserved her right "to support amendments that seek to further increase religious protections".
It is unclear when Senator Paterson will introduce his bill into the Upper House for debate or whether he will use the plan as the basis for amendments to Senator Smith's version.