The controversial gay marriage law of the ACT Parliament will be challenged in Australia's High Court in less than a week before the first same sex wedding ceremonies are set to take place. The federal government has contested the ACT law, and a two-day hearing is scheduled on Dec 3 and 4, according to Chief Justice Robert French. Reports said it was possible that the High Court will deliberate on the matter when the first same-sex marriage in Australia commence on Dec 8.

Chief Minister Katy Gallagher had previously warned that same-sex couples will have to wait a fortnight for the law to be formalised. They were also advised to wait another month after registering their names for the ceremonies.

The Marriage Equality Act 2013 has been approved in the ACT Legislation Register. ACT Attorney-General Simon Corbell said he had signed the law to allow the act to take effect on Nov 7. He said same-sex couples who are planning to get married can do so by Dec 8.

The High Court will begin deciding on the eight legal questions on the act. The Commonwealth of Australia challenged the gay marriage law because it believes it is not in line with the federal Marriage Act. Attorney-General George Brandis had insisted it is the only single law on marriage in the country.

The ACT will argue that states and territories can pass marriage laws for same-sex couples. Mr Brandis said he was looking to set the hearing at the earliest possible date to reduce any kind of stress that same-sex couples may experience if the Commonwealth succeeds in its plan to contest the law.

Prime Minister Tony Abbott will have to decide whether the proposed marriage equality law should be blocked. He has the power to challenge the ACT law in High Court or not allow it by putting it to a vote in both Parliament houses.

Same-sex marriage advocates in Australia said states and territories have the constitutional power to legalise gay marriage based on a Tasmanian report. The Tasmania Institute of Law Reform has published a report in response to an upper house vote in same-sex marriage legislation in Tasmania in 2012.