New Zealand Prime Minister Jacinda Ardern says refugees on Manus Island will be her sole focus when she meets with Malcolm Turnbull again this week.
But Ms Adern's criticism of Australia's handling of the refugee crisis on the island - which she has described as unacceptable - has prompted a warning from New Zealand's opposition for her to tread carefully.
Ms Adern on the weekend blasted Australia's handling of the issue as unacceptable as she continues to to push New Zealand's offer to accept 150 refugees and asylum seekers from Australia's offshore detention centres.
The NZ prime minister made the offer during her first face-to-face meeting with Mr Turnbull in Sydney a week ago.
She wants a more substantive conversation at the East Asia Summit this week.
"I see the human face of this and I see the need and the role New Zealand needs to play. I think it's clear that we don't see what's happening there as acceptable, that's why the offer's there," she said.
It was her strongest statement to date against the unfolding crisis and one she backed up again on Sunday night.
"We have grave concerns over the situation on Manus Island but also for the refugees on Nauru and that our hopes it to lend a hand as far as we are able in helping to resolve the situation," she said.
Ms Ardern will be pressing Mr Turnbull again to accept New Zealand's offer to take 150 refugees from both Manus Island and Nauru.
But National's foreign affairs spokesman Gerry Brownlee said it was "surprising she's decided to go so hard on the Australians".
"All I would say is recognise there is a whole lot of things at play here, not the least of which is these were people trying to enter Australia illegally," he told AAP on Sunday.
He said giving asylum seekers New Zealand residence could give them a back-door into Australia.
"What I do know is that one of the concerns the Australians will have is if these people come to New Zealand and they get residence here, and then of course because New Zealanders have pretty much free access into Australia they have back-door way into Australia."
