The ACT government will amend its proposed same-sex marriage legislation to bolster it against a High Court challenge by the federal government.
Legal experts argued a bill, which will be debated in the ACT Legislative Assembly on Tuesday, was in danger of being overturned because it sought to allow marriage for any person who cannot be married under the federal Marriage Act.
This would have been broader than bills in Tasmania and NSW where it was proposed to create an entirely separate form of marriage for same-sex couples.
ACT attorney-general Simon Corbell says the bill will be clarified to no longer cover transgender couples who do not identify as male or female.
"We recognise that the views of a number of constitutional experts are that we should put that issue beyond doubt," he told reporters in Canberra on Monday
The title also will be changed to specifically refer to "same-sex" marriage.
Mr Corbell said if the bill was upheld after being challenged in court, the ACT would later look at expanding its scope.
ACT Chief Minister Katy Gallagher remains committed to having the legislation passed this week.
Federal attorney-general George Brandis has asked Ms Gallagher not to proceed with the bill, which could allow the first same-sex marriage ceremonies to be held in the ACT in December.
Prime Minister Tony Abbott has said there should be a uniform approach to marriage across the country.
Meanwhile, Mr Abbott's sister Christine Forster has revealed her engagement to her partner of six years Virginia Edwards.
Ms Forster, a Sydney city councillor, has told New Idea magazine she was looking forward to walking down the aisle and her brother attending the wedding.
