Peter Dutton has verbally abused the first group of refugees to leave Australia’s offshore detention centres for resettlement in the United States, labelling them “economic refugees” – a term that does not exist in domestic or international law.

Fifty-two refugees this week left offshore detention on Manus Island and Nauru for resettlement in the US.

Sydney radio host Ray Hadley put to the immigration minister during a regular interview on Thursday that a photograph of the group published by News Corp this week looked like a fashion show on a catwalk in Paris or New York.

“They’re economic refugees, they got on a boat, paid a people smuggler a lot of money, and somebody once said to me that we’ve got the world’s biggest collection of Armani jeans and handbags up on Nauru waiting for people to collect it when they depart,” Dutton told 2GB radio.

Dutton claimed many of those who ended up in the island camps had not come from war-ravaged areas but were instead seeking economic advantage. They had received “an enormous amount of support” from Australian taxpayers for a long time.

Dutton’s comments contradict statistics from his own department.

Some 1,780 of the 2,000 people currently held offshore have been found to be refugees under the 1951 refugees convention, to which Australia is a party. Those refugees have been found to have a “well-founded fear of persecution” in their homeland. They cannot be returned there and are legally owed protection.

Among those being resettled in the US, are refugees from Sudan, which has been riven by brutal internecine wars for decades, Somalia, which has experienced near-constant conflict since the 1980s, and Myanmar, where the country’s military is undertaking an ethnic cleansing operation of the Rohingya minority, forcing more than 400,000 people to flee.

However, Dutton said conditions in offshore detention – which were ruled illegal by the Papua New Guinea supreme court – were not as bad as had been portrayed.

“We have been taken for a ride, I believe, by a lot of the advocates and people within Labor and the Greens who want you to believe this is a terrible existence,” Dutton said.

“These photos demonstrate otherwise. People have seen other photos in recent weeks of those up on Manus out enjoying themselves outside this centre, by the beach and all the rest of it.”

Dutton said he had long predicted once people were off Manus Island and Nauru “they’ll start to tell a very different story about how it wasn’t that bad”.

“There is a very different scenario up on Nauru and Manus than people want you to believe,” he said.

Amnesty International labelled the comments extremely irresponsible.

“They also show a complete lack of understanding of the refugee convention,” refugee co-ordinator Graham Thom said in a statement.

He said Dutton was putting at risk the opportunity for vulnerable and traumatised refugees to be safely resettled in the US.

“It is absolutely despicable that Peter Dutton would risk that by downplaying the acute vulnerability of these refugees at a time when the US is looking to cut its humanitarian program to its lowest level in over a decade,” he said.

The four years of Australia’s second iteration of offshore detention – which has cost nearly $10bn – have been plagued by consistent revelations of physical violence including murder, rape and sexual abuse of women and children, allegations of torture by guards, medical neglect leading to death, and catastrophic rates of mental health damage, self-harm and suicide attempts.

More than half the countries of the UN have criticised Australia’s offshore regime as an abuse of human rights.

United Nations bodies have consistently condemned Australia’s policies. On separate occasions, the UNHCR has described offshore detention as “immensely harmful”, “contrary … to common decency” and “dire and untenable”. The special rapporteur on torture said Australia’s regime was “cruel, inhuman and degrading punishment”.

And the Australian Senate said the government had “failed” to provide a safe environment for refugees and asylum seekers. In June, the Australian government agreed to pay $70m in compensation for illegally detaining people on Manus Island and holding them in dangerous and damaging conditions.

In response to Dutton’s comments, Labor’s immigration spokesman, Shayne Neumann, said to him via Twitter: “Instead of worrying about fashion, you should do your job and find 3rd country resettlement options for all eligible refugees.”

Refugees held on Nauru and Manus Island arrived in Australia as long ago as 2012 and were transferred to offshore detention under a strict government policy to block anyone who arrived by boat from entering the country.

They were recently cleared by US authorities for resettlement under a deal struck between the former Obama administration and the Turnbull government.

Up to 1,250 refugees are expected to be resettled in the US, but the US refugee deal is not expected to clear the Australian-run camps. Those held there remain Australia’s legal responsibility.

• Australian Associated Press contributed to this report