Opposition leader in Australia Tony Abbott says he can't bind his party for all time in opposition to same sex marriage.
After New Zealand passed gay marriage laws last week, New South Wales Premier Barry O'Farrell called for a reversal on Mr Abbott's decision to deny his MPs a conscience vote.
Mr Abbott has restated his support for the orthodox definition of marriage.
But he has hinted at the possibility the coalition could have a new approach after the federal election in September, which opinion polls indicate he is likely to win.
Mr Abbott says what happens will depend on the view of the post-election party room.