Greens count the cost of Turei controversy

Metiria Turei has survived another day in politics but the Green Party is counting the cost of a controversy which has dragged out for more than three weeks.

And the Greens can expect to take a hit in the polls following their tumultuous week.

Pollster Stephen Mills says the Greens have always had supporters who believe they're in politics for the cause, not the perks of being an MP.

The past week has probably seen those beliefs disappear, and made the Greens look like a regular political party, he says.

Mills told Newstalk ZB's Mike Hosking that's likely to be reflected in a drop in the polls.

"I'd say they'd be bracing themselves for a reasonably big fall from the 14's to 15's they were recording before," he said.

"New Zealand voters always seem to punish disunity, and I think it's quite unexpected from the Greens as well, part of their brand is idealism."

Labour is straining to distance itself from its likely coalition partner's troubles.

Leader Jacinda Ardern's attempts to take National to task over its record on transport and housing in Parliament were overshadowed yesterday by questions about her party's relationship with the Greens.

Turei stood firm in the face of a rebellion by two rogue MPs who resigned in protest at her decision to stay on as co-leader after revealing historic welfare fraud.

She said there was nothing that would make her step down as co-leader before the September 23 election. Even a drastic drop in the polls would not force her to reconsider her leadership, she said.

"I'm committed to stay at least until the election ... I know I have the support of my party and the support of my caucus."

After a long caucus meeting yesterday, the Greens announced that senior MPs Kennedy Graham and David Clendon had withdrawn from the caucus and would play no further part in the campaign. The party will hope their withdrawal puts an end to the controversy.

Graham and Clendon suggested there were others in the party who were upset about Turei's actions, but they admitted that they were the only members of caucus who felt strongly enough to resign. It is understood five party members have also quit over Turei's actions.

Green Party candidate for Hutt South Susanne Ruthven is withdrawing after taking a job in the public service, which is a conflict of interest. She made the announcement at a candidates' debate last night.

National was relishing the distraction yesterday. It even used the Green Party's crisis as leverage for a new fundraising drive.

"In the last 24 hours, we have seen even more chaos from the left with two MPs resigning in protest from the Green Party," an email from campaign chair Steven Joyce to supporters said.

"We don't want this dysfunctional group to take New Zealand backwards."

The Green caucus did not follow through on threats to suspend or expel Graham and Clendon for undermining the party.

Shaw admitted he was angry at them when he proposed expulsion, and had changed his mind after a good night's sleep.

Their voluntary withdrawal was a better resolution. "We just want to let them go out with some dignity."

The party's general manager, Sarah Helm, was also told off for publicly criticising the two departing MPs on Monday.

Additional reporting: Newstalk ZB