New Zealand Prime Minister Jacinda Ardern has confirmed the previous government's offer to take 150 refugees from Australia's offshore detention centres still stands, as Manus Island detainees warn of rapidly deteriorating conditions.
Ms Ardern will discuss the Manus Island stand-off with Prime Minister Malcolm Turnbull when they meet in Sydney on Sunday.
Some 600 asylum seekers and refugees have barricaded themselves inside the mothballed complex, which officially closed on Tuesday, fearful they will be attacked if they venture outside.
"I think anyone would look at a situation like that and see the human face of what is an issue that New Zealand is in the lucky position of not having to struggle with, (as) Australia has,' Ms Ardern said on Thursday.
"I am looking forward to having a conversation directly with the prime minister on Sunday about some of those issues, and New Zealand's role in and view on Manus Island in particular."
New Zealand, which takes a total of 750 refugees a year, made the resettlement offer under John Key's government in 2013.
It has been rejected, more than once, on the grounds that it would give refugees a backdoor into Australia and become a marketing opportunity for people smugglers.
Iranian refugee Behrouz Boochani, who is on Manus Island, says "the place is like a war zone".
He said detainees spent the night digging for water, while others kept watch to protect the camp in case of attack.
"Last night the refugees were in a dark place. People were lying down on the floor and were struggling with serious hunger, having not eaten since Tuesday," Mr Boochani told AAP from Manus Island on Thursday.
"At the same time, they were struggling with tropical mosquitoes. Now, malaria is a new worry to add to the many other risks the refugees face."
Staff have abandoned the camp, power and running water has been cut off, and the last food packs were distributed on Sunday night.
While the Australian government says food, water, electricity and medical services will be provided at alternative accommodation on the island, the UN's observers on Manus say arrangements are insufficient.
It called on Australia to urgently take responsibility and put a stop to the unfolding crisis.
Immigration Minister Peter Dutton is blaming advocates and the Greens for the ongoing stand-off.
"The advocates who are here telling them not to move, they are not doing those people any favours," he told the Nine Network on Thursday.
"I want to close Manus Island as quickly as possible. It doesn't help when you have got the Greens telling people not to engage and move. It makes a difficult situation even worse."
The Papua New Guinea defence force says it is just providing security outside the centre on the naval base to ensure there is no looting.
"We will not take part in the negotiations or the movement of the refugees still in the processing centre," Lieutenant General Fred Aile told AAP.
He said defence would not act without orders from Port Moresby to intervene but there was a likelihood something might happen.
"We do have personnel on Manus Island to assist if there is anything beyond the current situation at the moment," he said.
Human rights lawyers have lodged an injunction in the Papua New Guinea Supreme Court, which would effectively force the centre to re-open. The case is expected to be heard on Thursday.
The Lombrum centre was forced to close after the court ruled last year that Australia's detention of refugees and asylum seekers there was illegal and unconstitutional.
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