National Party leader Todd Muller says his caucus' position remains that it cannot work with New Zealand First.
Last night's latest 1 News Colmar Brunton political poll had support for National up nine percentage points to 38 percent, while Labour fell to 50 percent.
Speaking to Morning Report in the wake of the poll, Muller said: "My position has always been that our caucus in February said that we can't see a way that we would work with them.
"That remains our position. But I have said all along, my final pronunciation on all of this will be before the campaign starts."
At that time, he would also discuss National's position on working with the ACT Party.
In the meantime, the party has unveiled its slogan for the upcoming elections on a billboard in Napier today.
It reads: "Strong Team More Jobs Better Economy".
NZ First's strategy 'not working'
University of Auckland politics professor Jennifer Curtin told Morning Report in the lead-up to the election, New Zealand First was playing its traditional strategy.
"It's not working. And I think this is partly because this has been a different kind of coalition for New Zealand First than what they've experienced before.
"What I think they've done wrong here is they haven't made the most of the Provincial Growth Fund.
"They haven't spent all the money they have been allocated and Labour gave New Zealand First an opportunity to be the champion of the regions and to shore up their vote through a positive campaign and they've gone back to this traditional negative way of working.
"And actually, it looks like it's not going to work for them."
Public press relations consultant and and former National government press secretary Ben Thomas told Morning Report "National's long-term future is best - looks best - if New Zealand First is out of Parliament.
"On the other hand, they might be tempted. Muller has a background and a history with Winston Peters going back to the '90s in the Beehive. I think they will be at tempted to at least keep that option open.
"New Zealand First has a lot of headwinds coming into this election. The first one is their very low polling rate now, the second one is immigration, their usual go-to policy is just off the table right now because no-one is coming into the country. And the third thing is that SFO (Serious Fraud Office) inquiry.
"The benefits or the advantages they have is they may not have made the most of the Provincial Growth Fund. Well, Shane Jones has $3 billion to spend in the lead-up to the election on shovel-ready projects, so let's not count them out yet, but things aren't looking good."
Good results for Muller
Curtin said the poll results were what Muller needed.
"He had to bring National's vote share up to the high 30s and do it fairly quickly, and that's about shoring up the base."
Thomas said the results were "clearly just National base voters coming back".
Muller's approach was a tack back towards the centre with less hard-line rhetoric, Thomas said.
Clark could keep hurting Labour
Curtin thought the result was more of a reset, although still positive for Labour.
"They really really are going to have to be careful about how much more negative coverage that Clark can take without it actually damaging the reputation of the government...
"If the media keeps showing Clark in a negative light, then there is a hard decision for the government to make on this."
Thomas said this election would be different because of Covid-19, and that meant that health would be front and centre - and so would Clark.
"That plays into National's hail mary strategy which is knowing that it's unlikely they can match leader versus leader ... they're going for the strategy of saying 'we've got a better team, look behind the leader'."