Foreign Minister Nanaia Mahuta has defended her decision not to alert Prime Minister Jacinda Ardern to the imminent deportation of a 15-year-old boy from Australia, when she was told last week.
The circumstances around the deportation of the minor - described as "complex" - are still being kept private, but Mahuta has signalled he is not a 501 deportee.
Australian Department of Home Affairs has outlined a range of circumstances under which someone can be deported, but would not say which one applied to the boy.
He is in managed isolation being supported by two Oranga Tamariki staff onsite.
It is the latest incident to ratchet up trans-Tasman tensions, which the Opposition says have not been so bad since the Muldoon years.
Ardern only found out about the boy yesterday after media inquiries, but Mahuta was informed by Australia last Wednesday.
Mahuta says the right people at the time were alerted to what was an "operational matter".
"I can absolutely assure you when I was informed of the issue ... and there are privacy matters I will not discuss ... the care of the child was at the forefront of my decision making."
Deputy Prime Minister Grant Robertson was not critical of that decision, saying it was being dealt with as a consular matter.
He told reporters they may go back and "have a look and see if there was an opportunity to say anything earlier than that ... but ultimately it was being handled by the agencies you'd expect it to be".
National Party leader Judith Collins says relations have not been at "such a low ebb" in 40 years, and Ardern needs to "refresh" the relationship with Australia and its Prime Minister Scott Morrison.
"I think there needs to be one of respect," she told reporters.
"You can't get treated well as a country if you don't give respect. So Damien O'Connor going off and telling the Australians to pull their heads in ... is that really Damien O'Connor's job to do that? No is the answer."
She also had a crack at the senior Australian government minister for his comments last week about 501 deportees.
"It was a pretty poor call for minister Peter Dutton to come out and start talking about sending out the trash to New Zealand in the same week that we were commemorating what happened with an Australian who came here and killed 50 odd people in New Zealand and injured so many more.
"That's pretty hardcore, and actually speaks a lot about the lack of goodwill that I'm seeing at the moment," said Collins.
The government insists the relationship is fine, with Mahuta saying the lines of communication remain open.
"The prime minister speaks to PM Morrison, on a regular basis, on the issues that we want to work together on, that we need to work together on.
"I also speak to my counterpart on a fairly regular basis, again, on the issues that we look to work together on and other ministers engage with Australian counterparts ... so I wouldn't say that it's an all-time low."
Australian Department of Home Affairs says it approaches visa cancellation of minors with a "high degree of caution and consultation" and "complies with its legal obligations in circumstances where the removal of a minor is considered, including those under the Convention on the Rights of the Child".
Mahuta says New Zealand has had no advice suggesting Australia has breached any international law.