Chief Minister Andrew Barr says he will actively campaign for a "yes" vote in the postal survey on same-sex marriage, and will provide extra support for the gay community during the debate.
Mr Barr will bring a debate to the ACT parliament on Thursday, saying the postal survey planned by the federal government is already proving hurtful and divisive, forcing LGBTIQ Australians to "endure an unnecessary debate about the validity of their relationships and families".
The vote had been designed by people who did not want same-sex marriage to be legalised, and was a waste of $122 million, he said.
"To LGBTIQ Canberrans, I say this - you are not alone in the fight ahead," he said.
"There is great strength in our argument that all Australians should be treated equally under the law.
"We did not want to be in this situation; we did not want to have to engage in this divisive debate just to get equal rights. But now we are here, we must continue that campaign. Now is the time to make our voices heard."
Asked what he meant by extra support for the LGBTIQ community during the debate, he said the government was working with community groups "to supplement and enhance existing supports and resources", and would "seek to build a community coalition of support for marriage equality by working with organisations such as universities, business groups, the union movement and the not-for-profit sector to promote Canberra as Australia's most inclusive city".
Mr Barr began his chief ministership in 2014 by promising to fight for the rights of LGBTIQ people, telling his long-term partner Anthony Toms in the parliamentary gallery, "Anthony, I love you and I look forward to the day when we can legally marry in this country."
He urged Canberrans this week to "support love over hate and to vote yes to marriage equality".
"LGBTIQ Canberrans should have the same opportunities for love, commitment and happiness as everyone else."
Mr Barr has confirmed that all of Canberra's Labor politicians would vote yes in the postal survey.
The Greens' Shane Rattenbury and Caroline Le Couteur say they will also vote yes, despite believing the survey "shonky".
The Liberals are divided, with Jeremy Hanson and Nicole Lawder having previously declared their support for same-sex marriage. Mark Parton and Elizabeth Lee will also vote yes. Liberal Leader Alistair Coe will vote no, along with Vicki Dunne, Giulia Jones, Andrew Wall and James Milligan and Elizabeth Kikkert. Steve Doszpot has refused to give his view, saying he doesn't need to disclose, like any other citizen.
The ACT briefly legalised same-sex marriage in 2013, before the High Court overturned the law.