The leadership of the National Party is set to come down a vote.

MPs will select a new leader at a caucus meeting about 3pm this afternoon with an announcement expected before the end of the day.

Former Air New Zealand boss Chris Luxon appears to have the numbers over former party leader Simon Bridges.

But Newstalk ZB Political Editor Barry Soper told Mike Hosking Luxon hasn't managed to strike a deal with Bridges to avoid a leadership vote.

“They clearly were trying to broker one over the weekend. They kept talking yesterday, but as of this morning there’s been no deal which would turn to indicate they will simply be putting it to the vote.”

Soper says simply having to have the vote will be bad for the party as a whole.

“If Bridges did win, Luxon would always be seen as the leader in waiting, columns would continue to undermine him. It's a difficult situation.”

If successful, Luxon is expected to pick Nicola Willis as his deputy.

LISTEN ABOVE