An Australian politician proposed to his partner during a parliamentary debate on a bill to legalise same-sex.

Tim Wilson, a member of the conservative coalition, used his speech to propose to Ryan Bolger, who was watching from the public gallery.

"In my first speech I defined our bond by the ring that sits on both of our left hands," Wilson said. "There's only one thing left to do: Ryan Patrick Bolger, will you marry me?"

The 33-year-old primary school teacher’s "yes" was recorded in the official record.

The debate in the House of Representatives came as all the major parties push for legislation to be passed this week. Last month, a majority of Australians endorsed legalising same-sex marriage in a postal vote.

The Senate has already approved the bill and rejected proposed amendments that would have increased legal protections for those who would discriminate against gay couples on religious grounds.

However, several politicians, including Prime Minister Malcolm Turnbull, want the amendments returned to the bill.

Turnbull, a gay marriage supporter, says he wants wedding celebrants, not just those affiliated with churches, to have the right to refuse to officiate at same-sex marriages.

Should the House support the amendment, then new bill would return to the Senate for ratification, which would delay the legislation.

"The bill which the Senate passed is a robust bill, a whole range of religious protections are already in place," said Warren Entsch, a long-term advocate of marriage equality who helped draft the bill.

"We have made sure that we have removed any element of discrimination in this bill while ensuring that religious freedoms are protected."

Entsch said amendments to protect freedoms of speech could be introduced in separate bill, and should not be used to delay the reform.

"Australians are sick of excuses and they're sick of delays," he said.

However, Turnbull told parliament ”must not fail to recognise that there is sincere, heartfelt anxiety about the bill's impact on religious freedom."

"That is why I will support several amendments to the bill which will provide that additional reassurance in respect of their fundamental rights and freedoms," he added.