Thousands protest for Manus Island refugees

Australia's Federal Labor says Prime Minister Malcolm Turnbull must ask President Donald Trump to speed up the resettling of refugees in the US as the stand-off at the Manus Island detention centre enters a fifth day.

More than 600 refugees have barricaded themselves in the mothballed detention centre, which closed on Tuesday.

Food and drinking water has run out and the group is too scared to move to alternative accommodation in the main township out of fear they'll be attacked by locals.

The last food packs were distributed on Sunday.

"Turnbull is meeting with President Trump in coming weeks, in Asia, he should raise again the possibility of taking some people," said Opposition leader Bill Shorten.

"There is something going on at Manus which is deeply disturbing to the Australian people."

Rallies were held in Sydney and Melbourne yesterday to call for an end to the stand-off. Hundreds of people gathered at Hyde Park in Sydney where they heard there was no safe place for the refugees to go.

Nicole Judge, who worked for the Salvation Army at the centre, said she had advocated for closing Manus Island but didn't want refugees and asylum seekers to be left there.

In Melbourne CBD, recorded messages from men who remain inside the detention centre were played to a rally of hundreds of supporters.

"We are forgotten people who have been tortured ... even though we have committed no crime," one of the men said in his message.

The groups have called for the refugees to be resettled in Australia.

Previously, the Obama administration agreed to resettle up to 1250 people from Nauru and Manus Island.

President Trump has reluctantly agreed to honour the deal, and so far about 50 people have gone to the US.

Turnbull is meeting with New Zealand's leader Jacinda Ardern in Sydney today. She has repeated a previous offer to resettled 150 people, and Shorten backed that plan.

"The Government should accept that offer. Where you have got 600 people without food and water for days, the Government needs to take an active interest in their welfare."

Immigration Minister Peter Dutton said this week that the three alternative locations for the detainees were much better facilities than the closed centre, despite claims at least one was still under construction.

"The advocates who are here telling them not to move, they are not doing those people any favours," he told Nine Network on Thursday.

New Zealand, which takes a total of 750 refugees a year, made the initial resettlement offer in 2013 to the then Labor Gillard government.

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.

Meanwhile, the United Nations human rights office has called on Australia to restore food, water and health services to the group on Manus Island.