The Minister for Indigenous Australians, Linda Burney, is holding out hope both the Liberal Party and Greens can be convinced to enthusiastically back the 'yes' campaign for an Indigenous Voice to Parliament.
The Liberals and Greens are both actively weighing up their positions, attempting to accommodate strong views held in their respective partyrooms as they head into the first parliamentary sitting week for 2023.
Both parties are expected to arrive at a final position over the next few weeks, while the Nationals have already declared their opposition.
Debate over the Voice dominated political discussion over the summer break, with the Opposition demanding more detail on the proposed model for a Voice to Parliament.
The Greens' First Nations spokesperson, Lidia Thorpe, openly criticised the Voice while calling for a treaty to be the priority.
Ms Burney said she remains confident both parties can back the 'yes' campaign.
"I am very hopeful that both the Liberals and the Greens will come on board, I can't see any reason why they wouldn't," she said.
"This is about two things. It's about giving Aboriginal people a voice in matters that affect us, and it's also about lifting up the whole country.
"Those that don't come on board are holding the country back."
Asked if having the Liberals campaigning against the Voice would damage the campaign, she said the Liberals would only damage themselves by taking such a position.
"I think it would be more damaging for the Liberal Party to campaign against the Voice, quite frankly," she said.
Liberals call for detail as Bandt backs Thorpe
Senior Liberal figures maintain it will be hard for the party to come to a conclusion without the details previously demanded by Opposition leader Peter Dutton.
Mr Dutton has maintained his call for 15 questions on the structure and operations of the Voice, sent in a letter to the Prime Minister in January, to be answered.
Indigenous leaders of the 'yes' campaign say not all of those questions can be answered ahead of the referendum.
Liberal frontbencher Jonathan Duniam said the party will make its call when it has the information it wants.
"I think that it's right to expect that the government will detail exactly what's proposed here, put it out there for public consumption by the Australian people, what this means in totality," he said.
"I think Australians deserve that, they're a very mature population.
"So when we have that detail, which is what we're asking for on behalf of the Australian people, we'll be able to come to a position as a party room and move forward from there."
The Greens spent much of last week on a retreat in Victoria discussing the Voice, among other issues for the year ahead.
Greens leader Adam Bandt said there is still a way to go before they reach a final position.
"During the course of this week in Parliament, we're going to consider the position on a Voice to Parliament further," he said.
"We've been very clear that we want to see action on all elements of the [Uluru] Statement from the Heart, and sought some further information from the government, particularly around issues like sovereignty."
It is possible the party will come to a position where it supports the Voice, while allowing Senator Thorpe to maintain her opposition.
Mr Bandt said in that circumstance he hopes she would continue to serve the party as First Nations spokesperson.
"I support everything that Senator Thorpe has done," he said.
"With respect to following the rules of our party, she's got the right to vote differently.
"It would be my preference that she continues as our First Nations spokesperson. As the leader, that's something that I will get to decide."
