National's "troubles" over Jami-Lee Ross are a matter for the party and its leader, Prime Minister Jacinda Ardern says.
National's leader Simon Bridges yesterday released a report on the leaking of his expenses details, pointing the finger at Mr Ross. In the minutes before press conference - Mr Ross put out a series of inflammatory tweets accusing Mr Bridges of activity relating to donations, which Mr Bridges strongly denied.
"Thankfully these troubles are ultimately a matter for the opposition," Ms Adern said.
"No political party is free from these.
"Ultimately it's up to each individual leader how they choose to deal with them."
Ms Ardern said it was also up to National whether it would use the waka-jumping legislation.
The legislation, passed last month, was strongly opposed by National.
"We saw [the legislation] as being important to ensure that when people vote for an MP... particularly list MPs under the banner of a party if they're expelled from that a party where does that leave the voter if they've got an outcome that wasn't what they voted for," Ms Ardern said.
"If they [National] chose to expel one of their caucus members, if they chose not to use the waka-jumping legislation, they would then sit as an independent within Parliament."
Should there be a by-election in Mr Ross's generally National-supporting Botany seat, Ms Ardern said Labour would put a good effort into the the campaign if it chose to contest it.
Under the Electoral (Integrity) Amendment Act, if the caucus voted to expel Mr Ross he must be given 21 days to respond and Mr Bridges must also be able to show that the MP had acted in a way that distorts the proportionality of Parliament and is likely to keep doing it.
Petrol prices and climate change
Ms Ardern said despite the government's aim of moving away from from fossil fuels, this year's rapid petrol price rises were too tough on families.
"We do need to transition, but transition is the key word there.
"We've always talked about doing that it in such a way that it's not jarring, particularly for our low income families, or in fact for this issue for our middle income families who are feeling that squeeze.
She said the government excise on fuel was being used to create alternative transport options.
"When I talk about a transition, that that means that people will have the option of using public transport, lower emissions options, in some cases those don't exist yet for people.
"We need things like electric vehicles at a lower price point.
"That's why this jarring increase in fuel prices is pretty tough when we haven't established enough alternatives."
Asked about US President Donald Trump's comments casting doubt on whether humans are responsible for the earth's rising temperatures, Ms Ardern said the international community had to continue with the plans to meet the Paris climate agreement targets, while raising any inconsistencies with other members of the community.
"In the 10 years since I've been in politics by and large everyone has moved on from questioning the science."