Australia's ruling Coalition may offer its members a free vote on gay marriage.

Liberal Party Communications Minister Malcolm Turnbull has signaled that the Coalition, which includes the Liberal Party and its partner, the National Party, will probably let legislators vote as they choose on the issue.

“The Liberal Party and the Coalition generally should allow a free vote on the issue of same-sex marriage, or marriage equality, and I support that,” Turnbull said in a Sky News interview. “I think it is likely that we will, but as [Prime Minister] Tony Abbott has said, it's a decision for the party room and not for him.”

“People of the same sex can get married in Auckland and Wellington, Toronto, Ottawa and Vancouver, in New York and Los Angeles, in Baltimore, in Cape Town, but not in Australia. It does start to look as though we are the ones out of step,” he added.

The move comes less than a week after the federal government challenged a marriage law approved by lawmakers in the Australian Capital Territory (ACT). Australia's highest court struck down the ACT's marriage law just days after it went into effect, saying that it ran afoul of the federal Marriage Act, which limits marriage to heterosexual couples.

(Related: Australian court invalidates ACT marriages of gay couples.)

Rodney Croome, the national director for Australian Marriage Equality, said that allowing a free vote would boost the chances of passage.

“With a cross-party conscience vote, reform has a fighting chance, but the outcome at this stage is very unpredictable,” Croome told BloombergBusineesweek. “That's why it's so important that people who support reform in each of the different parties work together.”

Tanya Plibersek of the opposition Labor Party has pledged to introduce a same-sex marriage bill if legislators are allowed a free vote.

“Mr. Abbott moved to stop same-sex marriage in the ACT and the High Court has said it's for Federal Parliament to decide,” Plibersek told The Age. “So now, the prime minister needs to give his MPs a conscience vote on this issue so that the national Parliament can do just that.”