A national vote on whether to legalize same-sex marriage was effectively killed Tuesday when the main opposition bloc in Parliament said it wouldn’t support holding the ballot.
Prime Minister Malcolm Turnbull promised before national elections in July to hold a plebiscite on gay marriage if re-elected, in part to mollify critics within his own conservative ranks. After securing a narrow victory, he announced last month that hiscabinet had agreed to hold the nonbinding vote on Feb. 11 to test public support.
But Bill Shorten, leader of the main opposition Labor party, said his lawmakers had decided unanimously to block the legislation setting up the vote when it reached Parliament’s upper house, where the conservatives don’t have a majority.
Although the Labor party favors legalizing same-sex marriage, he said a publicly financed campaign would be costly and, more seriously, risk stoking social tensions around gays and lesbians.
“We could make marriage equality a reality today by having a free vote in the Parliament and that is what should be done,” Mr. Shorten said, announcing his party’s decision while surrounded by same-sex couples and their families. “This is the quickest, cheapest, least harmful and most certain path.”
A majority of Australians—around 60%, according to recent polls—support same-sex marriage, including the prime minister, who in March became the first Australian leader to attend Sydney’s gay and lesbian Mardi Gras parade.
But the issue has revealed deep divisions in Mr. Turnbull’s conservative Liberal-National coalition, which has a fragile grip on power. Opponents include Mr. Turnbull’s predecessor Tony Abbott, a former trainee priest whom Mr. Turnbull ousted last year in a party coup.
Mr. Turnbull, seeking to avoid renewed leadership tensions in a country that has churned through five prime ministers in six years, told reporters after Labor’s announcement that he would go ahead and present the bill.
But without the support of Labor, which holds 26 seats in the Senate, the government, which has 30 seats, would find it difficult to gain the 39 votes needed to approve it. Several minor-party lawmakers who support same-sex marriage oppose a nationwide vote, while right-wing parties oppose changing current laws.
Same-sex marriage has been recognized across much of Europe and the Americas, including the U.S., but New Zealand is the only country in the Asia-Pacific region to have legalized it. Ireland last year became the first country to legalize it by popular vote.
Opponents of same-sex marriage in Australia had already begun to mobilize. An internet campaign by a group called the Marriage Alliance claimed gay marriage would drive up suicide rates. The vote was also opposed by churches and the 50,000-strong Australian Christian Lobby.
