The Greens have confirmed the party will back the Yes campaign in this year's referendum on an Indigenous Voice to Parliament.
Just hours after senator Lidia Thorpe confirmed she would leave the party, the remaining Greens MPs and senators met to confirm their position on the issue.
The party will support the Yes campaign and back government legislation required ahead of the referendum expected late this year.
Greens leader Adam Bandt said they still believed the government should pursue a treaty before a Voice to Parliament but said opposing the referendum would be counter-productive.
"The Greens still strongly believe that a treaty should come first. We have secured commitments from the government that they will proceed with truth and treaty as well as Voice, and we will be holding the government to account on this," he said.
"I don't think a No vote will get us closer to treaty and truth, but I respect that others in the First Nations community may have a different view on that.
"I will join my fellow Greens MPs in campaigning for Yes."
Senator Thorpe quit the Greens party room earlier on Monday after struggling to find common ground with her former colleagues on the Voice.
She said she wanted to "speak freely on all issues from a sovereign perspective", unconstrained by the party's broader view on topics.
The Greens have noted that Senator Thorpe would have been able to vote differently under party rules, and Mr Bandt has expressed his regret that she opted to leave.
He said the Greens would now work to ensure the Yes campaign was successful.
"We want the referendum to succeed, we want First Nations justice, and we want truth and treaty as well as Voice," he said.
"The referendum will be an opportunity for the country to show its support for First Nations justice.
"A strong First Nations body would be a further step towards true self-determination and justice."
Labor and the Greens are now both formally supporting the Yes campaign, while the Nationals will oppose the referendum. The Liberal Party remains undecided.
