The Greens leadership has confirmed they will emerge from Government-forming talks with the Labour Party by Friday with a deal in hand.

But it will be up to a group of high-ranking Greens' members to decide whether the deal offered up by Labour is good enough.

If not, and the membership votes it down, the Greens will be sitting in the Opposition benches for the next three years.

Greens co-leaders James Shaw and Marama Davidson emerged from the second round of formal negotiations with Labour this evening.

Those talks were progressing well, according to Davidson. But neither her, nor Shaw, would outline what was actually talked about during the hour-and-a-half-long meeting.

"We are working hard and we are moving forward," Davidson said.

She did, however, reveal that the pair are hoping to have an agreement by Friday – that's a sentiment echoed by Prime Minister Jacinda Ardern.

But that does not mean the process is finished.

After formal talks are done, the Greens co-leaders will take the deal back to a committee of its high-ranking delegates to vote on whether or not it's accepted.

If more than 75 per cent of those on the conference call support the deal, it will formally be adopted.

But if not, Shaw confirmed that the Greens would not go back to the negotiating table with Labour.

Rather, the Greens would move into Opposition and Labour would govern alone.

"It's a straight up and down vote – we would either join the Government or we would not join the Government," Shaw said.

It is unclear how long it would take the delegates to vote, but Davidson said that in 2017 – the last time the leadership took a deal to their members – it took a matter of hours.

A spokesman for Ardern said it is also her intention to wrap up talks by the end of this week.

This means Ardern would announce her Cabinet early next week.

But there is still a bit of water to go under the bridge between now and then, according to Shaw.

He said there would be meetings between the Greens and Labour camps every day this week, including tomorrow.

At the moment, both sides are "stepping through" the areas which they are discussing.

But both Labour and the Greens are happy with how the talks are going so far.

Shaw noted that the fastest a Government has formed under MMP has been 12 working days.

"We're moving as fast as we can," he said before adding that forming Government is a "complicated business – there is a lot of detail."

Meanwhile, Labour will hold a caucus meeting tomorrow, by Zoom rather than in person.

After farewelling the MPs who are not returning last week, National MPs will also meet for a caucus meeting tomorrow – they will, however, be meeting in person.

Leader Judith Collins will then meet with MPs individually to discuss potential portfolio options.

Collins has said she will not announce her new line-up until after Ardern has announced her Cabinet.

A confidence vote in Collins as leader will not take place until the caucus meeting after the final election results are released. She is not expected to be challenged as a leader.