Winston Peters says there is still work to be done with both parties before NZ First can make a decision.
The New Zealand First leader said they had got a lot of work done and the board's engagement was complete and it was going home.
Peters said further discussions were needed with the leaders of both National and Labour.
The board had not reached a consensus on a final decision, but there was consensus on "the policies put to both sides and how far we've got".
"We have two sets of policy arrangements, they're obviously different because they're different parties. The board knows precisely what they'll both mean depending on what we do, if we take that choice."
Peters said some differences in calculations and opinions still had to be worked out with National and Labour.
"And we can't make a decision as a party until we've had those discussions.
He said once firmer agreements were ironed out NZ First would have to go back to the board and caucus for a sign-off.
That could be done by teleconference.
He would not say how long that would take or give details on what else had to be covered off.
"It's the form of things to come in the future."
He said on policy matters "we are 98 per cent of the way there."
He said there were two sets of policy proposals from each party but would not say which appealed most.
Asked if the party now had policy demands that it would "stick to its guns on", he said: "That's the shape of things, yes."
He said the form of Government, such as a coalition or a confidence and supply agreement or sitting on the cross benches, was yet to be discussed and all options were still on the table.
Peters said the party was still on track for an announcement before the end of the week.
"The board is starting to wind its way home and we're going to go away and try and bring the matter to a finality as fast as we possibly can."