With an announcement due, Winston Peters said earlier today his party has still not yet decided whether to go with National or Labour.
The party's MPs are still meeting at Parliament to consider the deals put forward by both National and Labour.
Look back on how we got here, follow RNZ's live coverage and find out what you need to know.
Labour and National MPs were also briefed this morning about the general nature of the deals that have been presented to New Zealand First.
Mr Peters stopped and spoke to reporters on his way out for "breakfast" just after 1pm.
"We are not very far away from finality, and we're just going to have a bite to eat and come back and put it all on the table and make a decision".
It was "seriously difficult", he said, as there were "pros and cons" for every part of the decision New Zealand First had before it.
"And we've got one more chance to evaluate what it means - both ways."
Mr Peters with a member of the public Photo: AFP
He said the MPs would go back, there were "a few hours to go" and they hoped to complete it.
No negotiation ever ended perfectly, Mr Peters said.
"If it was the way you liked it you'd never have been in the negotiation in the first place."
He said communications with both Labour and National were continuing, but the two proposals were "seriously, substantially final".
The details of this afternoon's announcement had not been confirmed, including whether either the Labour or National leader would be present, he said.
"You won't believe this but our major focus has been on the decision, not what happens after it - I mean, events change when that happens and we don't want to claim to be in control of those."
He had not made a decision whether the parties would be informed of his decision before the announcement.
"The decision's everything, other matters are extraneous and they'll sort themselves out once we've made a decision."
Asked whether there any chance New Zealand First might not make a decision today, he said: "I hope not."
"We've set our minds to make a decision, but the reason I don't rule out things is because you never know what might go in the next couple of hours," he said.
"That's the nature and shape of politics, things change by the hour."
It was a "very, very anxious time" for his caucus, he said.
Later as Mr Peters left popular Wellington Vietnamese cafe Where's Charlie? he said he was feeling better about making a decision.
He said negotiations were still on going and they were still getting information.
He wouldn't answer questions about whether he would definitely make an announcement today.
