Chief Minister Andrew Barr on Thursday secured the ACT parliament's approval to promote the 'yes' campaign ahead of the postal survey on same-sex marriage.

Mr Barr said the recently established Office of LGBTIQ affairs would "activate" government assets, such as the chess board in Garema Place, to support the push for marriage equality, and use digital channels to encourage people to enrol to vote and return their survey forms.

The government would also boost funding to community organisations like headspace, the AIDS Action Council and counselling services to support people during what has already been a combative campaign.

Mr Barr, who was Australia's first openly gay state or territory leader, would not put a dollar figure on his government's support for the 'yes' campaign but said most would be "in-kind".

"I want to allay any concerns that I'm about to spend $122 million on this," Mr Barr said.

While Greens leader and road safety minister Shane Rattenbury floated the idea of a rainbow pedestrian crossing, like the one removed from Sydney's Oxford Street in 2013, Mr Barr said he was concerned about safety.

Instead, he suggested a rainbow-wrapped bus and rainbow murals in legal graffiti areas, on top of the rainbow flag already flying through the city.

Mr Barr confirmed the government would not be giving in-kind support to the 'no' campaign.

Opposition leader Alistair Coe, who is personally against same-sex marriage and will vote 'no', said it was "inappropriate" to spend ACT ratepayer money promoting either side of the debate.

"This is a federal issue and if there's any funding it should come from the federal government. It shouldn't be ACT ratepayers, payroll taxpayers, land taxpayers or people who are simply paying for their parking that end up subsidising either side of this debate," Mr Coe said.

"I think we need to remember there's a diversity of views in the ACT and regardless of what the outcome us we need to remember there are some Canberrans who are for gay marriage and some who are against it.

"I think it's inappropriate for the ACT government to use taxpayer money to advocate for one side of the argument. It's a federal issue and it should be up to the federal government to determine if there's public funding. My preference is no funding should go to either side of this debate."

However Mr Rattenbury said it was the "duty" of government to stand up for all members of the community.

"At the moment some of the members of our community are being discriminated against so I think there is a valid role for the ACT government to step forward and say we support this change, we want this change to happen in Australia and we want all the members of our community to be allowed to celebrate their love with whoever they want to celebrate it with," Mr Rattenbury said.

The debate prompted emotional scenes in the ACT Legislative Assembly on Thursday.

A usually reserved Mr Barr said the debate had already become "hurtful" and "divisive" and all Australians deserved to be treated equally before the law, regardless of who they loved.

Labor backbencher Chris Steel said he would love the chance to marry his partner of seven years.

He said as a politician has has to put on his "invisible armour" to deal with the often-personal criticism that comes with the job and he called on all members of the LGBTIQ community to "suit up".

The motion came days after marriage equality advocates, Safe Schools protesters and police clashed outside the Legislative Assembly.

Enrol by August 24 to vote in the postal survey on same-sex marriage here: aec.gov.au/enrol/