NZ First's caucus has begun meetings to discuss government options to present to its board - but there's still no clue as to when that might happen.

MPs arrived at parliament on Friday morning for talks which could take all day.

Newcomer Mark Patterson stopped briefly to say the discussions were being held with the highest integrity.

"At my level we haven't had any visibility about what's happening so we'll be looking forward to seeing what the options are," he said.

"We'll find out this morning."

Kingmaker Winston Peters and his negotiating team held final meetings with National and Labour on Thursday, going late into the night.

"I'm very, very pleased we've actually got it finished," Mr Peters told reporters.
"We've got a seriously comprehensive dossier from both sides."

Those dossiers contain details of the concessions offered by National and Labour that will allow NZ First policies to be implemented by the next government.

There's nothing in them about ministerial positions - Mr Peters says that's something that can be worked out later.

The NZ First caucus began a meeting on Thursday night to draft documents that will be presented to the board meeting setting out what the party will get from the deals offered.

That meeting is expected to continue for most of Friday.

Mr Peters has said the board meeting will be held in Wellington on Saturday, Sunday or Monday.

A firm date is expected to be set on Friday.

The Greens are essential to a centre-left government because Labour and NZ First don't have enough seats between them for a majority, but they've played no part in the negotiations.

Mr Peters insisted on negotiating only with National and Labour, leaving it up to Labour to deliver the Greens' support.