Prime Minister Jacinda Ardern heavily criticised the way Australia treats New Zealanders living in their country - all while standing next to Aussie PM Scott Morrison.
Ms Ardern had been under pressure to address deportations and the rights of Kiwis in Australia this week.
During a joint press conference in Sydney today, Mr Morrison spoke of the strong relationship between the countries in times of need such as the Whakāri/White Island explosion, the Australian bush fires and the March 15 terrorist attack.
Ms Ardern acknowledged the cooperation during the disasters and attack, but said that "friendships aren’t just reaffirmed in times of tragedy, they must stand up to the test of politics".
"And in the face of politics, the New Zealand and Australia relationship is being tested."
She called New Zealanders "Australia's best migrants".
"But rather than them being given security to keep contributing, in return their rights have been eroded."
She called them "simple rights", and used the examples of people being unable to call on assistance from the national disability insurance scheme - "even though they pay into the scheme’s levy".
They also cannot join the defence force or become federal civil servants.
"Kiwis want to contribute to the place that is now their home. But they’re not being given the potential to do that to the fullest."
Ms Ardern then moved to deportations.
Australia's 2014 law deports people who commit crimes back to New Zealand - even if they have spent most of their lives living overseas.
"Send back Kiwis, genuine Kiwis - do not deport your people, and your problems.
"We will own our people. We ask that Australia stop exporting theirs."
She spoke of people with a tenuous link to New Zealand being sent here, and finding they have little to no connection to their new homeland.
When asked if the deportation policy was corrosive to the relationship Mr Morrison said, "you commit a crime here, you’re convicted, once you’ve done your time we send you home".
"That policy is framed in Australia’s national interest."
On if he would change the policy, he answered "no".
Ms Ardern then said there were "countless who have no home in New Zealand, they have no network, they have grown up in Australia and that is where they should stay".