New Zealand First has wrapped up its final meeting with Labour, ending five days of back-to-back meetings with the two major parties.
New Zealand First's caucus and board will get to consider proposals from both National and Labour when they finally meet to decide who to support in government.
Party leader Winston Peters confirmed Thursday was the last day for talks with both major parties, with two rounds of meetings with each.
He said no ministeral positions or roles have been canvassed with either National or Labour, and that will be discussed with his caucus in a meeting that will likely last all day Friday.
He said he would not be meeting face to face with the two parties again, and any futher correspondence would be conducted by phone and text.
Mr Peters said he did not know when he would be able to announce his decision as he still has to work around the commitments of some of his board members, to bring them together to consider the proposals.
Earlier on Thursday, he said it was unlikely they would be able to meet tomorrow to sign off a deal.
"It depends upon the logistical availability of the board, which could be Saturday, Sunday or Monday. I'll know that before too long."
Mr Peters said the board members had to come from all around the country.
They had also ruled out holding the meeting via Skype.
Mr Peters was asked why his board could not convene more quickly, given his comments earlier in the week they were on standby.
"This country's the same size as Japan, the same size as the UK, we're not a little island nation, so it takes people time to organise things, particularly since we're coming up to Friday, Saturday, Sunday."
Mr Peters also said he had to work around board members who have things like funerals to attend.
When the board does meet, he said they would get to consider proposals from both major parties.
"We'll take an analysis that's agreed upon, by both sides as to what they want, for us to consider as a board and as a caucus when the time comes."
Mr Peters said he was not leaning one way or another.
"I said I would go in with a totally open mind, I've asked my caucus and my board to have the same approach."
Final discussions between New Zealand First and National, and then with Labour, were held at Parliament on Thursday.
Labour leader Jacinda Ardern emerged from the party's latest meeting with New Zealand First saying it was important to take the time necessary to make a considered decision.
The process had been "robust" and the parties had discussed important policies where they both agreed and disagreed, she said.
"It's a given that this process should take some time," she said.
"We need to make sure we're making a considered decision about the future of New Zealand."
It was "only reasonable" to take this length of time to ensure the relationship was strong and that they had built consensus.
"This is about the kind of government that's going to be created to govern New Zealand over the next three years."
Ms Ardern said she had no criticism of the process and it had been led well.
"It has been a solid process, a good process, one that we've entered into in good faith and continue to participate in in good faith."
Former Green MP urges party to stand firm
Meanwhile, Labour is negotiating separately with the Greens, whose seats would be needed to form a government with New Zealand First.
Sue Bradford - who was a senior Green MP between 1999 and 2009 and quit after the party chose Metiria Turei as co-leader over her - urged her old party not to "go soft" in their coalition negotiations with Labour.
While Ms Bradford had no inside knowledge of the negotiations, she did have some advice for the Greens.
"I'd really be pushing hard to make sure there were some serious policy gains in areas that are a priority for the Green Party."
She said making sure there were Cabinet roles as part of any deal would also be important.
"It's much stronger to actually be inside the Cabinet itself, even if some of the positions were subsidiary to the main ministers - you'd hope the Greens would bargain for at least one full ministry, if not more."
Unless the Greens bargained hard for policy gains, it would not be worth them entering a deal, Ms Bradford said.
"There's always a danger with the Greens of going soft and of compromising too much ... I'm really hoping they're hanging tough."
A Green Party reference group, which includes current and former MPs, will help formulate the final deal to be presented to 170 delegates in a Special General Meeting.
It is likely to be a "take it or leave it" situation for the delegates.
If delegates oppose or seek to block the deal, and the meeting cannot reach a consensus, the agreement would then have to be put to a vote, which would need 75 per cent of the support to proceed.