National Party leader Judith Collins has been rolled after a vote of no-confidence by the party caucus after her sudden demotion of Simon Bridges.
Bridges is not ruling out putting his name forward for selection as party leader when the caucus meets again on Tuesday to select a new leadership team.
Collins demoted Bridges last night and stripped him of his portfolios for an alleged serious misconduct incident involving an exchange with MP Jacqui Dean five years ago.
Today Collins was voted out as National's leader after a more than three-hour party caucus which say a successful vote of no confidence passed against her.
Deputy party leader Dr Shane Reti told media he would be the interim leader until the next caucus meeting on Tuesday to decide the make-up of a "fresh leadership team".
Reti said the "caucus was concerned with the content of the press release" issued by Collins about demoting Bridges.
He refused to disclose what private conversations he had with colleagues about the matter and declined to disclose the exact details of the "serious allegation".
"We're looking for our new leadership team on Tuesday to bring us back in focus," Reti said.
"This is a business for the party, it is a business for MPs," he added.
"My job at the moment is to shepherd and guide the caucus through to the leadership decision next week."
Western Bay of Plenty councillor and National Party member Margaret Murray-Benge said she was "stunned" by Bridges' sudden demotion
"I'm appalled. I think Simon is a really fine fellow and while I don't know what the exact allegation involves, he does not deserve to be treated like this. No one does.
"Simon is an open and honest guy, he's a highly intelligent, hardworking and committed MP. He's a young man with all the ingredients to become a great leader of this country.
"I have been a great fan of Judith and I like them both. But this is a huge blunder on her part."
National Party Central North Island chairman and Bay of Plenty regional councillor Andrew von Dadelszen said he was "stunned" by Bridges' sudden demotion.
"This is just despicable. I have 100 per cent confidence in Simon and he has my support, without a shadow of any doubt.
"Simon has always operated with a straight bait and he's a great guy. This is a despicable act that smacks of desperation."
Bridges earlier today described Collins' behaviour as "truly desperate" and said it showed she would go to any lengths to hold on to the leadership.
It is understood that the allegations of "serious misconduct" relate to crude comments Bridges allegedly made at a function about five years ago.
Bridges is understood to have been talking with a group of about three fellow MPs, including Jami-Lee Ross and Todd McClay, when Dean walked past and the Tauranga MP called to her and made the comment.
However, Newstalk ZB political editor Barry Soper told Mike Hosking he understood the comment Bridges made was not directly to Dean but she had heard it.
The comment related to a sex technique to conceive a girl, Soper said.
Dean complained about it at the time and Bridges was spoken to by then deputy leader Bill English. Bridges had apologised, Soper said.
In her press statement last night Collins said the decision had been made "with the unanimous support of the board of the National Party".
"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 said.
"This decision has not been made lightly. However, the seriousness of the situation demands a swift and decisive response.
"Under my leadership, the National Party will not tolerate harassment and intimidation of any person."
Former National MP Bob Clarkson said it was "absolutely ridiculous" that the incident from five years ago had been bought to the surface.
"That thing that happened should be dealt with at the time. Not come back all those years later.
"There must be more to it, there has got to be something in the background."
Ngāi Te Rangi's chief executive Paora Stanley said he felt "shattered" for Bridges, who he described as a "good man" who had served Tauranga for many years.
He believed Collin's move was an "undermining of her own mana" as the party leader.
"It is pretty sad. The guy has been around for a long time, he is experienced."
Stanley said in general he believed National needed to be "a lot more open about how they're traversing within politics".
National MPs have shared mixed views about what unfolded.
National MP Simon O'Connor - who is married to Bridges' sister - told Newstalk ZB's Mike Hosking: "Judith Collins must resign".
He said her behaviour amounted to "bullying" and was damaging the party.
Mark Mitchell described Collins' actions as "deeply disrespectful".
Shadow Treasurer Andrew Bayly, a close Collins ally, would not say if he had confidence in Collins but said he still had faith in his party, saying "it's a great party".
National MP Barbara Kuriger said she was "proud of members of our party".
Rotorua councillor Tania Tapsell, who ran for the National Party in last year's election, said she did not want to comment.
Ngāti Whakaue leader Monty Morrison also declined to comment, as did Tauranga City Council Commission chairwoman Anne Tolley and Western Bay Mayor Garry Webber.
Tauranga Labour Party list MP Jan Tinetti said: We're in the middle of a global pandemic and the Government's focus is on managing that, not the ongoing leadership issues in the National Party."
Western Bay of Plenty District could have fewer councillors to vote for next election.