Prime Minister Christopher Luxon has given a scathing appraisal of the Treaty Principles Bill on the day of its first reading.
He said the legislation has been unhelpful to his mission of getting the country back on track.
Despite that, he said the National caucus would support the bill - championed by ACT's David Seymour - this afternoon, but no further, fulfilling National's coalition agreement with ACT.
Luxon will miss the parliamentary debate - enroute to Peru for the APEC summit instead - but he called a morning media conference where he criticised the legislation in perhaps his strongest words yet.
"You do not go negate, with a single stroke of a pen, 184 years of debate and discussion, with a bill that I think is very simplistic."
Seymour has previously criticised National's position, accusing its coalition partner of being afraid to engage with difficult issues.
But Luxon bit back, saying the Treaty Principles Bill was not helping the government's focus on the real "hard stuff" like the cost-of-living and rising crime.
"It's not helping us get New Zealand back on track," Luxon said.
"Go out here and talk to New Zealanders getting through a week. It's a tough time. It's getting better. Our plan is starting to work, but that's the hard work that the National Party is engaged on."
Luxon said National's long-held position was that it was more sensible to grapple with difficult issues on a "case by case" basis: "We can have a conversation respectfully without actually having to go into demonising each other."
He said the compromise position - where National supported the bill to select committee but no further - was a pragmatic approach given New Zealand's political system.
"I didn't get what I wanted, I've been very upfront about that. David Seymour and ACT didn't get what they wanted, which was a full national referendum."
Earlier this week, the Green Party requested the legislation be treated as a conscience issue, allowing individual MPs to vote as they please.
Luxon said that had not been a topic of discussion within National's caucus, but regardless, he would not have entertained the idea.
ACT's David Seymour responds: 'It very clearly is not distracting'
Speaking on Midday Report, Seymour disagreed with Luxon's assessment that the bill was unhelpful to the government.
"There wouldn't be a government without a coalition agreement to do this," Seymour said.
He said the record showed the bill had not stopped the government from cutting waste and regulation, as well as improving health and education.
"It very clearly is not distracting the government from doing those things because we're doing it."
Furthermore, the interpretation of Treaty principles were essential to how the government tackled many of the problems facing New Zealand, Seymour said.
"The task is all the harder when you have an assumption that people have a different role in society based on ancestry."
Seymour said he was feeling "fantastic" ahead of the first reading: "It's finally arrived that New Zealanders will have a proper discussion about what our founding document means."
