Labour and the Green Party say they are both prepared to work with New Zealand First after the election, but a referendum on Māori seats is off the table.
Labour's Māori campaign director, Willie Jackson, told Newshub's The Nation, Labour would first talk to the Greens, and everything was negotiable - except the Māori seats.
But he said if Labour needed New Zealand First to get into Parliament, it would work with its leader Winston Peters, despite his pledge to hold a referendum on Māori seats.
"Of course we can work with him ... everything is negotiable."
However, Mr Jackson said there would be no referendum under Labour's watch.
Green Party list candidate Marama Davidson said her party had worked with Mr Peters successfully and would do so again despite their opposition to some of his policies.
"We won't put up with some of his attitudes and policies and approaches that pull on that populist racism stuff that we need to be resisting."
Ms Davidson said it was the Green's preference to work with Labour and possibly the Māori Party, but Mr Jackson said Labour would prefer to not have to work with the Māori Party.