The idea that the Deputy Prime Minister role could be shared between two minor coalition party leaders has been criticised by a former member of Parliament - who believes the decision process could give insight into how the incoming Government will function.

Incoming Prime Minister Christopher Luxon has said he and other party leaders are in the “final stages of our coalition conversations”.

Luxon had confirmed there were still a couple of issues to work out and the role of Deputy Prime Minister was an example - the contest for the role now between NZ First leader Winston Peters and Act Party leader David Seymour – National Party deputy leader Nicola Willis is not in the frame for the job.

Former United Future party leader and political commentator Peter Dunne weighed in on the discussion over how the decision should be made.

Talking to The Mike Hosking Breakfast, Dunne was asked by Hosking if it was fair to say that the deputy role looks like a number two and Seymour couldn't afford to let Peters take the position, given his party got the larger share of votes.

"I think that's right," said Dunne.

"You can't have two people sitting on one seat - it's just not possible - and you could have two Deputy Prime Ministers but one will always be more senior than the other, that's what this is all about. "

Hosking asked if the counter-argument to Peters' request for the title might be his asking for Deputy Prime Minister and Foreign Affairs Minister, in the sense the minister role is often out and can't be deputised.

Dunne said taking this approach would be a recipe for confusion.

"Even from a practical sense in the House, one will have the number two seat and the other the number three seat - I think it's a bit of a nonsense actually."

There is quiet confidence among spectators of the negotiation talks that the deal will be officially completed today, particularly given the notion the deputy role was one of only a small handful of topics left to be discussed.

Dunne believed the process the incoming Government takes to resolve the remaining issues could give clues to what the country has signed up for ahead of the next parliamentary term.

"If it's going to be this sort of stand-off mentality for resolving issues then it doesn't look very promising," he said.

"Whatever the policy agreement, it's going to be the mechanics of practice that will be the test for most people."

However, Dunne believed the period of time taken to complete the talks has been acceptable and the focus will quickly shift away from the negotiation period.

"People will forget quickly how it was put together. If it does seem to be an awkward, cumbersome arrangement then that's a long-term problem for the Government right through its term," said Dunne.

"If it seemed to work smoothly and cooperatively, then they're off to a good start - but I think that's where the game shifts too."

It is understood Willis’ view is that it is up to Luxon to choose the deputy and she had made clear to him that she did not have any expectation of getting it. Luxon has made it clear she would be Finance Minister.

On the potential for co-deputy PMs, Luxon said yesterday: “There’s obviously been a number of options and conversations taking place, presented and discussed, but I’ll keep that in the room.”