Malcolm Turnbull is urging almost 600 men holed up inside the mothballed immigration detention facility on Manus Island to comply with Papua-New Guinea law.
A showdown is looming at the centre with PNG authorities warning they will use force to remove barricaded refugees and asylum seekers.
The men believe it's safer to remain in the compound rather than risk being attacked by locals at new facilities near the main township of Lorengau.
The prime minister insists the new facilities are fully-equipped and resourced.
"They need food, water, security, healthcare, they have all that spare," Mr Turnbull told reporters in the Vietnamese city of Da Nang where is attending the APEC summit.
They also needed to comply with PNG law, as did activists including Greens senator Nick McKim who were encouraging the men to stay put.
"They are acting in a way contrary to the interests of those refugees and other residents," Mr Turnbull said.
Local authorities posted a warning notice on Thursday.
"You are ... instructed to vacate this compound immediately," it said.
"If necessary, force may be used to relocate those who refuse to move voluntarily for your own sake."
Iranian refugee Behrouz Boochani said the use of force was unacceptable.
"We are not doing anything wrong, we are only resisting peacefully," he told AAP.
"We are asking again for freedom in a safe third country."
The UN's refugee agency says substantial parts of the alternative accommodation are not yet ready, a claim rejected by Immigration Minister Peter Dutton.
"The only difference in the new centre is that where we serve three meals a day at the (detention centre), we're asking people to prepare their own meals with food supplied and some think that that's not good enough for them," he said.