Sydney:
A conservative Australian senator was forced to resign from his parliamentary role on Wednesday after he linked same-sex marriage to bestiality and polygamy during a debate.
Speaking on the gay marriage bill before parliament late on Tuesday, outspoken Liberal Senator Cory Bernardi described it as "another tear in the fabric of our social mores".
"If we are prepared to redefine marriage so that it suits the latest criterion that two people who love each other should be able to get married irrespective of their gender... then what is the next step?" he said.
"The next step, quite frankly, is having three people or four people that love each other being able to enter into a permanent union endorsed by society.
"There are even some creepy people out there... (who) say it is okay to have consensual sexual relations between humans and animals. Will that be a future step?"
The comments sparked outrage in the ruling Labor Party and elements within the Liberal Party, including high-profile former leader Malcolm Turnbull who described them as "hysterical, alarmist, offensive" remarks.
Liberal opposition leader Tony Abbott said Mr Bernardi, a South Australian senator, had offered to resign his position as his parliamentary secretary as a result, and he had accepted this.
Staunch Catholic Abbott, who opinion polls suggest could become prime minister when an election is held next year, described Bernardi as "a decent bloke with strong opinions" but said his comments had been ill-disciplined.
"They are views that I don't share," Abbott told reporters. "They are views which I think many people will find repugnant."
Bernardi had been reprimanded by Mr Abbott in the past, notably for his comments on Islam in 2010 when he called for Australia to ban the burqa, the all-encompassing garment wore by some Muslim women.
Advocates of marriage equality say it has broad support in Australia, where same-sex unions are recognised in five states.
However, because marriage is covered by federal legislation which defines it as only between a man and a woman, couples united in civil unions are not seen as "married" by the national government.
Prime Minister Julia Gillard opposes legalising same-sex marriage, but has asked members of her party to vote on the issue according to their consciences.
The bill, however, is likely to fail given that the Liberal and National opposition are expected to reject it.