New Zealand’s opposition believes trans-Tasman relations have sunk to a 40-year low as a new front opens in the deteriorating relationship.

The deportation of a 15-year-old boy from Australia on a flight Home Affairs Minister Peter Dutton described as “taking out the trash” has infuriated Kiwi politicians across the spectrum.

New Zealand’s Greens have labelled Australia a “rogue nation” that “persistently flouts human rights laws”.

Before the emergence of the minor’s deportation, Foreign Minister Nanaia Mahuta said Mr Dutton’s comments “only serve to trash his own reputation”.

Ms Mahuta didn’t attack Australian counterparts further on Tuesday, saying authorities were focused on the needs of the child.

However, National leader Judith Collins, a conservative of the same political stripe as Ms Dutton, took aim.

NZ main opposition National Party has lashed Peter Dutton’s comments after the deportation.

Ms Collins said the deportation was inhumane and Mr Dutton’s comments were poorly timed given the second anniversary of the Christchurch Mosques terror attack on Monday.

“The 15-year-old no doubt has been involved in something they shouldn’t be involved in. But actually, you have to be human,” she said.

“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 … an Australian who came here and killed 50-odd people in New Zealand and injured so many more.”

The Australian terrorist, Brenton Tarrant, is serving his life imprisonment in an Auckland jail; New Zealand has no plans to deport him.

The row over the 15-year-old is the latest inflammation of tensions between the two allies.

A month ago, Prime Minister Jacinda Ardern accused Australia of “exporting its problems” amid an argument over a former dual NZ-Australian citizen who is allegedly aligned with ISIS.

But, whether its Australia’s deportation policy, different approaches on China, immigration and refugee settings or other issues, the gap between the two countries is widening.

Ms Collins believes relations haven’t been worse since the underarm bowling incident, when Kiwi PM Sir Robert Muldoon said “New Zealanders who leave for Australia raise the IQ of both countries”.

“I’ve never seen Australia and New Zealand relations at such a low ebb since the days of Rob Muldoon,” she said.

“Jacinda Ardern needs to refresh the relationship with Scott Morrison and that will help refresh the relationship between Australia and New Zealand at a government level.”

In one of her most decisive policy shifts since slumping to an election defeat in October 2020, Ms Collins has given National’s full-blooded support to a trans-Tasman travel bubble.

The bubble was first pledged by Ms Ardern and Mr Morrison last May, only to flounder due to outbreaks and a lack of agreement between governments.

National believes Kiwis are ready to reopen to the world.

“I think that there is a change in people’s sentiment,” Ms Collins said.

“If Australia can … then why can’t we?

“One of the things that New Zealand could do [to mend the relationship] is to open up the trans-Tasman border with Australia.

“Take the hand that’s being offered and friendship, instead of dismissing it and saying it’s all too hard.

“We need to rebuild our tourism industry before it dies, and we also need to reunite family members who can’t get together again.”

-AAP