Senior National MP Judith Collins says Jami-Lee Ross has displayed "delusional" behaviour and she is "fast losing interest in him as an MP".
Collins had been a supporter and ally of Ross but today's comments reflect the fury National MPs have with their colleague, who has been on sick leave for the past fortnight.
National MPs have arrived at Parliament ahead of a caucus meeting to decide the fate of "rogue" colleague Ross - with some savaging him for being "disloyal".
The sidelined MP was yesterday fingered as the person who leaked leader Simon Bridges' travel expenses.
But Ross is not going quietly, firing out several tweets yesterday denying being the leaker, accusing National of "unlawful" behaviour and claiming he had secretly recorded some conversations with Bridges before taking health leave from Parliament.
The National caucus meets this morning to decide what punishment to hand out to Ross, with suspension an option.
Collins told reporters on her way into Parliament she would have her say at caucus.
"The tweets yesterday and the admission of taping Simon Bridges as the leader obviously to use it against him at some stage was extraordinary and I have never in my mere 16 years in politics seen anything like it."
She described it as "delusional" behaviour, but she had never suspected it. "I was floored
Collins said she was not surprised by the strength of feeling from her caucus colleagues.
"We have a very united caucus and people are floored by this behaviour.
"I'm fast losing interest in him as an MP."
Senior MP Amy Adams said she "absolutely" had confidence in Bridges. She called Ross' tweets "extraordinary", saying she'd never seen anything like it.
"I think Simon's done an excellent job and he's got my full support."
Adams said there were questions to be asked from the report and from Ross' tweets.
"I value loyalty incredibly highly and I think our caucus values loyalty incredibly highly and we take a very dim view, obviously, when loyalty isn't shown."
Adams said she had no idea whether what Ross had claimed was true but she said it would be "very concerning behaviour" if he had taped conversations with colleagues.
"The whole series of events of the last few days raises important questions that are concerning and as I said, certainly unprecedented in my time."
Mark Mitchell also said he backed Bridges, and agreed with him that Ross was "lashing out" in his tweets.
Mitchell wouldn't be drawn on Ross' future before caucus met.
He revealed that he called Ross when it emerged he was standing down for health reasons.
"I definitely gave him a call when he was stood down for health reasons to make sure he was OK and to make sure his family was OK. He said he was focused on his recovery," Mitchell said.
"We should definitely be checking on his welfare and wellbeing because he's obviously fighting some health issues. So absolutely, we should remain focused on that.
"We also have to remain focused on the contents of the report and getting to caucus today and having a discussion around that."
Mitchell said Ross' tweets and recording Bridges were a clear attack on National's leader and were disloyal.
MP Alastair Scott said Ross would be gone if he had his way.
He didn't believe National would use the new waka-jumping law because they had voted against it.
Todd Muller said it was "a bit raw" that a colleague had lashed out in the way Ross had.
His personal view was that Ross could not stay in caucus. "I suspect from the sentiment that you've had over the last couple of hours with my colleagues, it's been a pretty consistent theme.
"At the very least I think suspension is likely to be the outcome."
Louise Upston said Bridges was not the subject of today's caucus meeting, but an "MP that's been going rogue".
She called Ross' tweets "absolutely shocking" and said he had to answer for his actions.
Todd McClay declined to speculate on what caucus might decide, saying that was a matter that would be discussed later this morning.
Asked whether he backed National leader Simon Bridges, McClay said: "Absolutely, 100 per cent. This is not a matter of leadership, its about one individual who has shown significant disloyalty to every caucus member."
McClay said Ross' tweets yesterday, denying the leak and threatening to expose "unlawful" behaviour within National, were inappropriate and incorrect.
McClay said the entire caucus was disappointed. "We've been working very hard over the past year. Again, this is about one person who has shown great disloyalty to caucus."
But he didn't believe Ross' actions had caused any damage to National.
Alfred Ngaro said he backed Bridges 100 per cent.
"Leadership is not about the chaos that confronts you, it's about what do you after that. And I think he's done the right thing."
Ngaro said Ross had been a good colleague and a good friend and he was surprised by his actions.
Melissa Lee said the caucus was united.
"We're a strong team and someone decided they're not part of the team."
Jonathan Young said Ross' behaviour was "very surprising", and there was strong support for Bridges.
MP Simon O'Connor declined to comment on his way in, saying they were matters for caucus to discuss.
"The caucus is quite united in the job that we have, which is holding the Government to account.
"It's disappointing that one person has let the caucus down."
Scott Simpson said he backed Bridges but he didn't know whether Ross would remain in the party.
"I do have a firm view and I'm happy to say that in caucus"
Simpson called Ross' tweets "reprehensible".
MP Chris Bishop said it was "gut-wrenching" that a member of the team had done what Ross did.
"Up until yesterday he was a member of the team and he's made it pretty clear from his actions yesterday with the tweets just before Simon's press conference that he's not acting like a member of the team," he said.
"Disunity in political parties is not a good thing as you know."
Michael Woodhouse said he was right behind Bridges, and called Ross' behaviour "highly disappointing".
He would wait to see what Ross had to say - if he turned up to caucus today - but said disloyal was an apt description.
Andrew Bayly declined to say how he might vote but said he fully supported Bridges.
"It's a test of how good teams are and I believe we'll show we will be an excellent, resolute team, fully united and know where we're going forward."
Matt King called the leak saga a "hump in the road" and caucus would deal with it.
"For us as caucus we're tight, we're unified, we'll get on with it. This is bigger than one man."
King said he was "disappointed with the whole thing".
MP Stuart Smith declined to comment on Ross but gave his support to Bridges.
Ian McKelvie said he didn't come into Parliament to deal with such "unfortunate sideshows". He didn't think it had affected Bridges' leadership at all.
Nikki Wagner called it a "blip" in the history of a strong party but offered no other comment.
Process to suspend an MP
Otago University Law Professor Andrew Geddis told Radio NZ today that the National Party's constitution contained no provision for suspension or expulsion from caucus - and that may come down to a simple majority vote on a motion.
But the constitution did contain provision for disciplinary proceedings such as revoking party membership.
"Those would govern that procedure," Geddis said.
But that was legally contestable. "If the party moves to expel you and you don't think it has grounds to do so or you think it's not following its own rules, you could go to court and challenge the party's proceedings there."
Geddis said if Ross went to the Speaker and said he wanted to be an independent MP, his seat in Parliament would automatically become vacant and there would be a byelection.
If Ross was thrown out of caucus, Bridges could invoke the party-hopping legislation and go to the Speaker and say Ross was distorting the proportionality of Parliament and ask to have the seat declared vacant.
Boag: Bridges will come out of this stronger
Former National Party president Michelle Boag told MediaWorks this morning that Ross was acting alone.
"I predict that today, Simon Bridges will emerge from the National Party caucus with the unanimous support of every other MP. Actually, I think this has been good for his leadership.
"I was one of those who thought there shouldn't be an inquiry because it dragged it on. Now I'm very glad there was," Boag said.
She called Ross' actions "very irrational".
"The people I feel for are his family. I feel terrible for his family because they get dragged into this, and the people who worked with him very closely in his electorate."
Boag said there would be no way back for Ross in the way Maurice Williamson had done following a similar issue years before. "I predict that Bridges will come out of this stronger than when he went in."
"Now we know what the problem is, everyone else will come in behind. Everyone else will be united," she said.
Boag said if Ross had any evidence of wrongdoing on the part of Bridges, he should go to police.
Ross 'burnt toast'
Former National Party press secretary Ben Thomas told Newstalk ZB's Mike Hosking he has no doubt about Ross's fate.
"Jami-Lee Ross is burnt toast. He is probably on a five or six setting toast, that someone has forgotten about, that is smoking in the kitchen."
Thomas said Ross' tweets have alienated him from any sympathy from the wider caucus.
"This isn't going to be a referendum on Simon Bridges. This is just going to be about Jami-Lee Ross' conduct."
Thomas said National could invoke the waka-jumping legislation to get rid of Ross.
"I don't think National will have too many qualms about using it to cut out a problem."
An investigation found Jami-Lee Ross was the leaker, however, Thomas said there should never have been an inquiry.
"Probability suggested it was always somebody within the National Party camp, and it is fair to say it has probably been mishandled at every turn."
Former Labour Party president Mike Williams agreed, telling Hosking the situation was out of control.
"This matter should never have been pursued in the first place but I think Simon Bridges needs to be very careful because you will always have, in a caucus of that size, someone going off the rails."
Bridges needed to sort it as quickly as possible, he said.
"You can't welcome him back ... after what he said. If you expel him, you risk a byelection because of the waka-jumping Bill. There's no good answer."
Ardern: 'Pretty tough' for National leader
Prime Minister Jacinda Ardern told Newstalk ZB's Mike Hosking that the situation for Bridges was "pretty tough".
When asked to assess how Bridges had handled the fallout of the investigation Ardern said she would not "sit here and rank performance".
She commented that the Labour Party had gone through its own issues during its time in opposition.