Indrika Ratwatte said the situation in Nauru, as well and Manus Island in Papua New Guinea, was as bad as he had seen in his 25-year career.

Both locations have been used to house more than 3,000 men, women and children from Afghanistan, Iran, Syria, Sri Lanka and Myanmar, since Australia implemented its offshore processing policy in 2013.

Speaking to journalists in Geneva after returning from Nauru last week, Mr. Ratwatte, who heads the Asia and Pacific bureau of the Office of the UN High Commissioner for Refugees (UNHCR), described the “shocking” psychological and the mental toll on refugees and asylum seekers.

Children have been particularly affected, he said:

“I have seen a little girl for example who was 12 years old in a catatonic state who has not stepped out of her room in a month […] clinical psychiatrists and professionals have determined that around 80 per cent of the asylum-seekers and refugees in Nauru and Manus as well are suffering from post-traumatic stress and depression. This is per capita one of the highest mental health problems levels that have been noted.”

Despite the clear need to address the problem, the lack of psychiatric help and healthcare “has increased the sense of hopelessness and despair,”  Ratwatte said.

“The point here is also that Australia has had a long tradition of supporting refugee and humanitarian programmes globally, but on this one, the offshore processing policy has had an extremely detrimental impact on refugees and asylum seekers.”

He urged Australia to continue to support the authorities on Nauru once it hands over responsibility to the island for medical and psychiatric services.

There are currently around 2,000 detainees on the islands.

Around 40 children born in Nauru have seen “nothing but detention-like conditions,” Mr. Ratwatte said, and another 50 youngsters have spent more than half their lives there.

Under a deal agreed between Australia and the United States, some 1,000 detainees from Nauru will be repatriated to the US Around 180 have already left the island.

Welcoming the agreement, the UNHCR official said that this would still leave the same number of people on Nauru, and he urged the Australian Government to consider an offer from New Zealand to rehouse them.

“It is a very genuine offer and New Zealand has an excellent programme for refugee settlement,” Mr. Ratwatte said.