New Greens Leader Adam Bandt insists he wants to work with federal Labor to kick the Morrison government out of power, despite an apparent row between the two parties in the Northern Territory.
The NT News says the Greens will preference the ALP below Territory Alliance and the Country Liberal Party in the upcoming NT Johnston by-election.
Federal opposition frontbencher Pat Conroy described the decision as "incredible", saying it would be a first.
"It's certainly remarkable that this first has occurred only a week-and-a-half after Adam Bandt was elected (the Greens) leader," Mr Conroy told AAP on Saturday.
"Given they have preferenced the Country Liberal party ahead of us, who are climate change denialists, I'm not sure what signal it is sending to their supporters."
But Mr Bandt told AAP that he wants to work with federal Labor Leader Anthony Albanese to remove the coalition government and put in place a "Green New Deal".
"Preferences are a matter for the local branches of the party," he said.
He said the NT how-to-vote cards are not handed out directly at polling booths, and it is up to voters where they put their preferences.
"The outcome of this by-election will not change who is in government in the NT," he said.
NT Greens say the move was punishment for Labor's decision to lift the moratorium on onshore gas fracking.
"We are encouraging our supporters to help sack the frackers by putting Labor last," NT Greens convener Jasmyn Sheppard told NT News.
The Greens will divert their first preferences to the Ban Fracking Fix Youth Crime Protect Water Party, then the independents.
They will put Labor below Territory Alliance -a party led by former CLP chief minister Terry Mills - and the CLP.
"Fracking the Betaloo Basin is like building the Adani mine and people in the NT are angry at Labor lighting the fuse on this giant carbon bomb," Mr Bandt said.