It is hard to recall a New Zealand Prime Minister being so critical of an Australian government.
But Jacinda Ardern was provoked by the Australian government's decision to foist one of its homegrown terrorists onto New Zealand.
Ardern has accused Australia of acting in bad faith for its decision to wash its hands of a woman, formerly a dual citizen of both countries, who joined the terrorist Isis group and who has turned up in Turkey with two young children.
Ardern did not exactly accuse Australia of being immoral when she unexpectedly unleashed her demarche in front of reporters at Parliament today.
But her tone suggested that the word comes close to what she thinks – and not without cause.
A 6-year girl left New Zealand for Australia, she was raised there by her family who are still there, she gained Australian citizenship there, was radicalised there and travelled to Syria on her Australian passport to join Isis.
The intelligence agencies of both countries knew it could be a looming problem if she survived, and Ardern raised it with Australian Prime Minister Scott Morrison in 2018.
Australia's response was to revoke her citizenship in 2019, ensuring it was New Zealand's problem alone to deal with.
For a country that prides itself on its "fair go" ethos, it fails to meet the test.
And that was reflected in Ardern's criticism of Australia's actions, after news that a so-called "New Zealand" woman, Suhayra Aden, had turned up in Turkey from Syria.
"We will put our hands up when we need to own a situation," Ardern said. "We would expect the same from Australia.
"They did not act in good faith," she said.
"I think New Zealand, frankly, is tired of having Australia export its problems."
Former National Foreign Minister Gerry Brownlee said New Zealand had to respect Australia's decision.
But there is a difference between respecting its right to make the decision, and the actual decision.
It is difficult to respect a decision that treats its neighbours with such disrespect.
Morrison told reporters in Canberra that the decision was on the basis of national security interests.
Ardern warned Morrison back in 2019 she would be going public with his decision, and then again this morning she reminded him that she would be revealing what sat behind the news.
It certainly puts some context to Ardern's statement in February last year when standing next to Morrison, she strongly condemned the Australian policy of deporting 501s – many of them criminals born in New Zealand but raised in Australia.
Australian and New Zealand leaders have been fond of saying that we are family – maybe so but this is turning into a long-lasting feud based on morality.
The one positive aspect of the feud is that at least the leaders are maintaining regular contact.