Australia's opposition Greens party and a human rights group are criticizing the government's decision to reopen a detention center for asylum seekers on Manus Island in Papua New Guinea.

Prime Minister Julia Gillard's government signed a memorandum of understanding with PNG Friday to open the Manus Island center for the processing of illegal immigrants seeking asylum in Australia.

Greens Senator Sarah Hanson-Young said Sunday that she wants a parliamentary inquiry into the reopening to answer questions, such as how much it will cost to reactivate the center.

The Refugee Council of Australia has called the policy of processing asylum seekers offshore “inhumane” and damaging to the immigrants.

Meanwhile, the Australian High Court began a hearing Monday that challenges the government's refugee swap deal with Malaysia.

Under the deal, Canberra would send 800 asylum seekers to Malaysia in return for 4,000 refugees being sent to Australia.