National’s Shane Reti is the new interim leader of the National Party, after Judith Collins lost the job, 1News understands.

She held the position for over a year.

The nation will find out on Wednesday when Auckland's border will open.

Collins was elected leader in July 2020, following Todd Muller’s resignation after 53 days in charge after he rolled Bridges.

It comes after a dramatic 15 hours – late last night, Collins released a statement informing the press Simon Bridges was being demoted following a complaint around a serious misconduct allegation.

“The case relates to comments made by Mr Bridges to a female caucus colleague at a function a number of years ago,” Collins said.

It is understood that MP is Jacqui Dean and the comment was allegedly made in front of Dean in 2017.

“Having been made aware of the seriousness of the complaint for the first time and the ongoing distress this has caused the complainant, I was left with no option but to immediately demote Simon Bridges and relieve him of his portfolio responsibilities.”

Collins was due to hold the media conference at 10am, after the 9am caucus meeting. After three hours news emerged Collins had lost her role. Reti, who was her deputy, has taken temporary charge until a final decision on leader is made next week.

Dr Shane Reti.

“I am pleased to say that I am just the MP for Papakura again,” Collins said on Twitter.

“It’s been a privilege to take over the leadership of @NZNationalParty during the worst of times and to do so for 16 months. It has taken huge stamina and resolve, & has been particularly difficult because of a variety of factors.

“I knew when I was confided in by a female colleague regarding her allegation of serious misconduct against a senior colleague, that I would likely lose the leadership by taking the matter so seriously.

“If I hadn’t, then I felt that I wouldn’t deserve the role. I didn’t ask for the allegation to be given to me. I am proud of the support I received from Dr Shane Reti, a man of principle, and I will continue to advocate, not only for Papakura, but for those who have no voice.”

Just after 7am, Bridges arrived at Parliament, telling media there was “a huge amount I want to say about what happened yesterday and how wrong it was”.

“I assure you I will but I want to talk to my caucus first and be very clear with them about what I think and about what I think should happen for the National Party,” Bridges said from outside Parliament.

Bridges told media it demonstrated Collins would go to “any length to hold onto the leadership of the National Party”.

National MPs then arrived at Parliament, with Simon O’Connor saying Collins’ actions and the handling of the situation was “downright appalling”.

1News political editor Jessica Mutch McKay said, prior to last night, National Party sources had been saying there was a “small chance” of a leadership change happening before Christmas.

But, the sources had said there was a chance of it happening after the New Year, she said.

“This development that’s come about, with Simon Bridges, has prompted a whole series of cards, if you like, falling down around it for the National Party.”

Because Parliament was heading into its Christmas break, the new leader will get a bit more breathing room, Mutch McKay said.

“But, if we’re getting a new leader for the party next week, they’re going to have to hit the ground running. We’ve still got three more weeks here in Parliament where they’ll have to face questions in the debating chamber.”

She said it was also a question of whether Botany MP Christopher Luxon would be taking his chance now, or whether the likes of Mark Mitchell or Chris Bishop could act as interim leader.

But, the latter option of an interim leader would be messy too, Mutch McKay added.