AUSTRALIA’S ruling party voted yesterday to endorse same-sex marriage, a reversal of its long-standing position.

However, the impact of the vote at the centre-left Labour Party’s annual conference was diluted by its endorsement of a motion by prime minister Julia Gillard to allow politicians to make a “conscience vote” on bills attempting to legalise gay marriage.

That means MPs can vote on the issue according to their personal beliefs rather than being forced to vote in line with the party line.

Gillard’s coalition government holds a wafer-thin majority in parliament over the conservative Liberal Party – which opposes same-sex marriage – and several Labour members personally oppose gay marriage. So any bill proposing to legalise gay marriage would still face a tough battle.

Polls have shown a majority of Australians favour allowing same-sex marriage, and several states already permit civil unions between gay couples. But Gillard opposes any changes to Australia’s marriage act, which prohibits same-sex weddings.

She called the party’s support of the conscience vote “the right decision”, but brushed off questions about its endorsement of the policy change.

“My focus was on the conscience vote and people should be able to vote in accordance with their conscience – and certainly now they will,” Gillard said.

Equality advocates were disappointed with the conscience vote, but praised as historic the policy change.

“The momentum toward marriage equality is unstoppable,” Australian Marriage Equality national convener Alex Greenwich said.