Australian rock icon Jimmy Barnes has added his famous voice to calls for asylum seekers on Nauru to be resettled in Australia, saying offshore detention was saddling Australia with an international reputation as one of the world’s worst violators of human rights.

“People are living in detention with no hope, with no future, nothing to live for, nothing to strive for, nothing to dream about, it’s criminal,” Mr Barnes told AAP at a rally in Sydney.

“The behaviour of our government and the government before it, our politicians, have been disgusting.”

As protesters gathered in cities across the country, Mr Barnes said he was worried Australia was becoming “a joke” on the world stage.

“My friends in America, they’re all fighting their own demons with Trump, but they all look and say ‘man your human rights record is worse than ours’,” he said.

“We should stand back as a country, the lucky country, and say ‘how can we help?’ Not be afraid.”

Barnes said he felt compelled to bring his family to the Hyde Park protest, attended by an estimated 1000 people.

In Melbourne protesters heard from a Nauru detainee who spoke of his five years watching his life slip away day by day as he languished on the remote tropical island.

Hyde Park protesters express their horror at offshore detention. Photo: AAP/Joel Carrett

In Melbourne, Refugee Action Collective co-chairman David Glanz said he and others felt they’d been hitting their heads on a brick wall.

“You ask yourself how we can be in a situation where children are resigning themselves to death under the so-called protection of the Australian government,” he told hundreds of supporters.

“Well today I think we can say we are beginning to see the cracks in that wall.”

The health of asylum seekers on Nauru has shot to prominence in the past few weeks, with Scott Morrison under immense pressure to bring sick children and their families to Australia.

Eleven children were airlifted from Nauru for medical reasons last week, but some 40 others remain. Photo: Getty

Eleven children were evacuated earlier this week, leaving 52 on the island.

Refugee advocates say another four kids have since left Nauru.

Mr Morrison said about 30 people had been taken off Nauru over the last few weeks.

“Those numbers have been coming down and we will continue to work on that,” Mr Morrison told reporters in Sydney.

“We have just been getting on and doing it like a responsible and compassionate government should.”

Federal Labor MP Anthony Albanese said ahead of Saturday’s rally that Australia could have strong borders “without losing our national soul”.

“The government isn’t moving fast enough … these are just little kids and they deserve, I think, a bit of compassion and a bit of common sense,” he told reporters in Melbourne.

He called on the government to immediately take up an offer from the New Zealand government – first made to Labor in 2013 – to accept refugees from those locations.

It can be done without special legislation to stop those who settle in New Zealand from then moving to Australia, he said.

-with AAP