New Zealand's being told to cut Australia out of an offer to take refugees stranded on Manus Island.

Papua New Guinea's Supreme Court ruled yesterday there was no obligation to restore services to the mothballed detention centre, which has around 600 detainees.

Amnesty International's Pacific Researcher Kate Schuetze said New Zealand's rejected offer to Australia should be made directly to the Asian nation.

"Clearly the courts said yesterday that PNG is in control. What we're saying is that Australia can no longer stand in the way of offers from other countries because the situation is so desperate."

Prime Minister Jacinda Ardern repeated New Zealand's previous offer to take 150 refugees in her meeting with Australian Prime Minister Malcolm Turnbull when they met on Sunday. 

Australia rejected the offer largely because of fears refugees resettled in New Zealand could cross the Tasman.

Schuetze said that while Papua New Guinea is in control of the facility, the refugee crisis is still an Australian issue.

"That doesn't absolve the Australian govt of it's liability. They're the ones still bankrolling this, they're the ones still managing the contracts here

The Manus Island detainees have now been without food, electricity or clean water for over a week.