The incoming Prime Minister has announced the newly forming Government has agreed to definitely deliver tax relief for lower-income households in New Zealand as the coalition talks enter what has been called an "important week".

Christopher Luxon told The Mike Hosking Breakfast there has been constant work done over the weekend for the three parties of National, Act and NZ First to form the next Government and progress has been made.

Luxon said while there's agreement on the big goals, there are differing views on how they should be achieved - one of which is the Treaty referendum.

He said the coalition talks have been a very thorough process.

"To give you a sense, Mike, we've gone through the manifesto and full policy programmes of all three parties - you're discussing each and every policy and line to go through it," said Luxon.

"You're understanding where the other parties are coming from, they understand where you're coming from and that takes time, but we've covered an awful lot of ground."

Act Party leader David Seymour told the media last week the coalition negotiations had reached the "80-metre mark", a suggestion that Luxon said could possibly be the case, however he wouldn't confirm exactly how far they were through talks.

Hosking pushed further on whether the country was facing another full week of parties negotiating.

"I'm not sure, but I was thinking the whole of this week is important to wrap things up," said Luxon.

"We'll go as fast as we possibly can through it but we don't know which day this week we'll emerge from this process and how much of it will be resolved."

Luxon rejected suggestions the other parties were attacking him during negotiations but did admit there were "crunchy" elements of the negotiations that required more discussion.

Hosking asked if tax in the referendum was one of the supposed crunchy components, Luxon laughed and said he wouldn't get into it.

However, Luxon was then asked if the incoming Government would be able to still deliver tax relief.

"Yep, I can tell you we are going to deliver tax relief as we talked about, to lower-income New Zealanders," he said.

Hosking asked if the approach might look a little different, to which Luxon said "correct" but reaffirmed the cuts would come.

"You start these negotiations and sit down with the players and personalities, with hopefully what is the next nine years - you're setting up what you hope will be a strong and successful government."

It was revealed at the end of last week that Seymour had finally met face-to-face with Winston Peters, but he admitted it could still be a while before a coalition deal is struck between National, Act and New Zealand First.

The Act leader told Hosking on Friday that there are still some substantive issues of disagreement.

He said that while a lot of work has been done, the last stage of negotiations could take a bit longer as the three parties need to get down to "brass tacks".