Rongotai MP Julie Anne Genter has apologised in Parliament after National accused her of intimidating and attacking one of its ministers in the House.
A spokesperson for the Green Party told RNZ her actions were "unacceptable" and fell short of the standards they expect of their MPs.
As MPs were debating roading projects as part of the Annual Review - Transport on Wednesday night, Genter rose from her seat and walked across the chamber towards National's Matt Doocey.
She then waved a book in his face and repeatedly yelled: "Read the report!"
The debate's chair, Parliament Deputy Speaker Barbara Kuriger, interrupted and urged the Green MP to resume her seat.
"We know that transport is one of those touchy subjects but if we want to get the best out of the minister, interjections are fine but it would be good if we could actually just ask the questions and let the minister answer them.... rather than shouting matches and it is not appropriate to get out of one's seat to go and have an argument with somebody on the other side," Kuriger said.
MP Julie Anne Genter stands over National's Matt Doocey in Parliament. Photo: Screenshot / Parliament TV
National senior whip Scott Simpson told the House that Genter's actions were threatening and unbecoming of Parliament.
"A few minutes ago, there was an incident that occurred in this chamber... that I have never seen before. It was unprecedented in my experience in this chamber.
"To have a member rise from her seat, stride across the House and then confront, in a most intimidating manner, a member of this chamber I think is utterly unparliamentary and warrants further investigation and sanction," Simpson said.
He then called for Parliament Speaker Gerry Brownlee to be recalled to the debating chamber and described Genter's actions as a "serious, intimidatory, physical attack upon another member".
"Sir, I have never seen behaviour of that sort in this chamber in my time in this House and I think its a serious matter that warrants an intervention immediately.
"That the member is still sitting in this chamber without having apologised or accounted for her actions I think is intolerable," Simpson said.
MPs in the House stood to inform the Speaker what they saw.
"I did not see any contact," said Genter's Green Party colleague Steve Abel, who admitted he did not see the incident in the House, but only caught the end on Parliament TV.
"I understand from my colleague that she feels strongly about the issue and wanted to show you the actual data in the booklet. She's a very science and data-driven human being."
Abel said when Kuriger intervened, Genter returned to her seat and remained in place.
National MP Dr Vanessa Weenink said initially some MPs found Genter's actions amusing, before reflecting further.
"Had that been myself sitting there, with either another female or indeed if a male was doing that to me, the way that would be viewed would be quite different. But I feel that no matter who it was, that was an extraordinary outburst and it was intimidating in its nature."
ACT's Karen Chhour agreed it was intimidating.
"It looked like a huge amount of intimidation that was going on, very close to the person, standing over the person, and physically shaking a book in that person's face. If that was me, I would have felt very intimidated and I feel that it was really inappropriate."
Julie Anne Genter in Parliament. File photo. Photo: Hagen Hopkins/Getty Images
Genter then rose and apologised.
"It was the last thing I wanted to do, to intimidate anyone in this House. What has absolutely motivated me is a desire to share information that I believe would be of benefit to everyone in this House, and I'm very sorry if in my passion to do so I was intimidating. That was not my intention."
Brownlee said it was not appropriate for any Member of Parliament to debate from the floor, or to take actions that could be considered intimidating.
"It doesn't reflect well on Parliament when we have these sorts of moments.
"If the member feels that her passionate feelings about the matters being debated are to such a point where you feel you need to intervene like that, I suggest quietly going out of the House would be a much better solution, and far more orderly than approaching anybody in their benches."
Scott Simpson told RNZ National would likely take further action.
"I suspect it certainly, possibly will occur. But we'll wait and see, I'll go and talk to some colleagues and take some advice."
"It was utterly extraordinary for a Member to stride from her chair in the chamber and then physically intimidate another member."
Simpson said it would be up to Doocey to say whether he felt threatened.
Doocey would not comment when approached by RNZ.
A spokesperson for the Green Party said Genter's actions were unacceptable.
"Julie Anne Genter's actions were clearly unacceptable and do not meet the standards of what we expect of Green Party MPs.
"The co-leaders have talked to Julie Anne and made clear their expectations. Julie Anne has apologised to the Speaker and to the House."