The United Nations’ High Commissioner for Refugees has raised serious concerns about the living conditions for asylum seekers being held at the Nauru and Manus Island detention centres.

In two damning reports it has called on the Federal Government to stop sending asylum-seeker children to the detention centres. It singled out the Nauru centre in particular, saying it is rat-infested, cramped, and very hot.

“It’s not appropriate for families and children to be transferred to Nauru or Papua New Guinea and the suggestions and proposals for transferring unaccompanied children for us is even more deeply concerning,” Richard Towle of the UN refugee agency said.

“Unaccompanied children are already very vulnerable and to place them in situations of uncertainty and tough physical conditions … could be very damaging to their health and well-being.”

Read the full UNHCR reports on Manus Island and Nauru.

The UNHCR report says that only one asylum seeker on Nauru has had a refugee claim processed in the past 14 months, and warns that a processing logjam may see asylum seekers stuck in the centres for years.

“People are being held in what we found to be mandatory, arbitrary detention settings,” Richard Towle said.

“The toughness of the physical conditions is superimposed on a mandatory detention environment and that compounds people’s uncertainty.

“If not addressed very carefully, we could see a fairly rapid degradation of psycho-social and physical health if people don’t have a fairly early determination of their fate and future.”

However, Immigration Minister Scott Morrison said many problems are due to the previous government.

“The previous government … kept changing its mind, taking people on and off,” he said. “Processing is now underway again, and we are looking to further progress in the months ahead.”

There are more than 1,700 asylum seekers being held in detention centres on Nauru and Manus Island.

The UN refugee agency visited both camps in October and says it is deeply troubled by a failure to process refugee claims.

Mr Morrison claimed the situation would improve in the future.

“We are working quickly with our partners in Nauru and PNG to put all the appropriate facilities in place,” he said. “It is a work in progress and we are making significant progress.”