Gay couples began marrying shortly past midnight in the Australian capital of Canberra as the nation's first gay marriage law took effect.

The Sydney Morning Herald reported on the marriages of Alan Wright and Joel Player, who exchanged vows beneath the 55 bronze bells of the National Carillon at Lake Burley Griffin, and Stephen Dawson and Dennis Liddelow. Dawson, a West Australian state politician, and Liddelow wed outside Parliament House.

At least 20 gay couples are marrying in Canberra this weekend, according to gay rights group Australian Marriage Equality.

However, the Australian Capital Territory's (ACT) marriage law might be short lived.

Upon passage in October, Prime Minister Tony Abbott, whose conservative Liberal-National coalition swept into power on September 7 on a pledge to lower taxes, filed a legal challenge to the law, arguing that only the federal government has the power to regulate marriage.

The Australian High Court announced last week that it would rule Thursday on the federal government's challenge.

“We don't know how long we've got in the sense that the High Court might overrule the laws next week, so we thought: 'Let's do it straight away and let's have the maximum amount of time being married,'” Dawson is quoted as saying by the AP.