CANBERRA, Australia (AP) — Australia's prime minister says asylum seekers who are allowed to leave Pacific island migrant camps to get medical treatment in Australia will be sent to a prison-like facility on a remote island.

Prime Minister Scott Morrison flew to Christmas Island on Wednesday to announce the strategy aimed at preventing asylum seekers from reaching the Australian mainland. Critics argue that the Australian island doesn't have the necessary medical facilities.

Australia pays Nauru and Papua New Guinea to accommodate almost 1,000 asylum seekers who have attempted to reach Australia by boat since 2013.

The government began reopening a mothballed migration camp in Christmas Island in December when political parties outside the government passed a law allowing doctors rather than bureaucrats to decide which asylum seekers can come to Australia for hospital treatment.