Australia aims to remove all asylum seeking children from Nauru within two months as concerns escalate about their deteriorating health after languishing on the tiny Pacific atoll nation for up to five years.

But Cabinet ministers said yesterday the government is maintaining its much-criticized policy of sending all asylum seekers who attempt to reach Australia by boat to immigration camps on Nauru and Papua New Guinea. Refugee advocates welcomed the change for children, 46 of whom were born in Nauru. Activists said there were only 38 children remaining on Nauru by Thursday. Papua New Guinea has male-only facilities and all asylum seekers there are adults.

Australia's top diplomat in Britain, High Commissioner George Brandis, told London radio LBC that the government expects all asylum seeking children to be moved from Nauru to Australia this year.

"There are hardly any children on Nauru ... and we expect that by the end of this year, there will be none," Brandis said.

Prime Minister Scott Morrison offered few details yesterday. Children have been transferred off Nauru, that's been happening for some time," Morrison told Sydney Radio 2GB.

"I haven't been showboating about it. I haven't been drawing attention to it. It's been done in accordance with our policies, our existing policies and I obviously don't go into the operational arrangements," Morrison added.

When Morrison took office in an internal government leadership ballot in August, there were 113 asylum seeker children on Nauru. Last week, the government said that number was down to 52.

Australia has all but ended the people-smuggling traffic from Southeast Asian ports since it announced that any asylum seekers who attempt reach Australian shores by boat from July 19, 2013, would never be allowed to settle in Australia.Pressure has mounted on the government to make an exception for children, but some government lawmakers argue that would only encourage asylum seekers to put children at risk by bringing them on treacherous voyages to Australia on rickety fishing boats.

The United States agreed in 2016 to accept up to 1,250 refugees from Nauru and Papua New Guinea. But after more than a year of screening, only 439 have found new homes in the U.S.

Asylum Seekers Resource Center Director Jana Favero said 47 children, plus 88 adult family members, had been brought to Australia from Nauru in the past two weeks, leaving 38 children behind. The children had been brought to Australia for medical treatment and none of the families had been told they could stay in Australia, she said.

"The condition of the children has been pretty shocking," Favero said. "We have seen children not eating or drinking for days, in a comatose state. The mental and physical conditions of these children on Nauru have been devastating."

Human rights lawyer George Newhouse said his organization, National Justice Project, had taken court action to bring around 50 children to Australia for medical treatment, including children who have been taken directly from the airport to intensive care units because their organs were failing.

"It's taken court hearings and a groundswell from the community to get the government to act to get these kids off Nauru," Newhouse said. "I've seen some of these children myself with matchstick arms and legs because they haven't been eating — imagery that you've seen in war," he added.