After a long day of waiting for NZ First to decide on their fate, Labour leader Jacinda Ardern and National leader Bill English are set to wait a bit longer as NZ First board talks carry on into a second day.

English and Ardern were in Wellington yesterday to wait as the NZ First caucus and board met for hours in the party's Bowen House offices at Parliament.

In mid-afternoon, a statement was issued to advise the meeting would be "several hours" longer and after 6pm media were told there would be no public statements and the board would return again this morning.

Although NZ First leader Winston Peters said he expected to announce NZ First's intentions as soon as possible after that board meeting, English said that even if NZ First made its decision on which side to go with there would have to be further negotiations before a final deal and government was settled on.

"They won't be looking at completed agreements because there are still a number of issues related to forming a government that have not yet been dealt with. The policy discussion was completed but there is not yet an agreement including the type of government, ministerial positions to put to our caucus or party board."

He said working out those final details should not take long although if NZ First continued to negotiate with both sides on those issues it could be more difficult because of the added "complexity" on the Labour side because of the inclusion of the Green Party.

English has not spoken about negotiations since last Monday and said NZ First had to push for what it could while it had the bargaining power to do so.

"Look at it from NZ First's point of view. They're trying to secure policy gains when they're in a position to do so because it's a bit harder once you're in government."

He believed National was in a strong position and the talks had also helped to test the relationships between the teams as well as policy differences.

"It was a way of testing whether the parties can get on, testing the relationships a bit and just seeing how they work together. That's all been really positive."

He said that was important because the parties in any government arrangement needed to be able to deal with each other "in an atmosphere of respect" to cope with matters that arose that had not been envisaged in a coalition agreement.

The nine NZ First caucus members and 14 board members were sequestered away for the day getting meals taken into them rather than leaving for food. The meeting broke soon after 6pm and the board left through a back entrance. Only NZ First MP Shane Jones left past the waiting media, saying they were going to get dinner.

It is not clear what the process will be in terms of NZ First advising National and Labour what its decision is once it has settled on it.

The Green Party has also again held off holding its Special General Meeting to seek 75 per cent approval from about 150 delegates for its deal with Labour. It has been ready to hold that meeting for days.

Peters said little during the day and would not confirm whether his discussions with one party were more advanced than another. He did confirm English was correct that he had not discussed ministerial portfolios in negotiations.

He has also said the board and caucus were yet to consider what form of government NZ First would settle on - from the cross benches to a full coalition.

Ardern refused to comment, saying only that it was before the NZ First board and that was an issue for that party.

Earlier, Peters had told Newstalk ZB it was a complex decision and all options for a government formation were still on the table - from the cross benches to a full coalition. He wanted the party to decide based on policy gains rather than ministerial roles.

He said NZ First had worked over the weekend to firm up the precise agreements with National and Labour, and contact had been "reasonably extensive".

But there had been no discussion on ministerial positions.

"The danger of these sorts of talks is when people get ahead of themselves and concern themselves with positions and preferment and things like that and policy gets sacrificed on the way through"