Refugees detained on Manus Island and Nauru considered to be of "adverse character" will be sent to Christmas Island if they try to come to Australia under new medical evacuation laws.
The Australian government has identified 57 individuals held in offshore detention that it alleges are accused of crimes including murder, child sexual assault, drug trafficking and terror activity.
The government has budgeted $US1 billion over four years to reopen the detention centre on Christmas Island, an Australian territory in the Indian Ocean.
Nobody has been brought to Australia under the new laws, which came into effect on Saturday.
Refugee advocates expect a handful of applications in the coming fortnight and argue there's no need for Christmas Island to be reopened.
Under the current government, about 900 patients and family members have been evacuated to Australia from offshore detention for health reasons.
UN rights chief calls for more humane process for refugees
The UN High Commissioner for Human Rights has called for a more humane approach by Australia to its offshore processing of refugees.
Michelle Bachelet made the call during an address to the UN Human Rights Council in Geneva.
Ms Bachelet said her office had raised concerns with Australia about the imminent transfer of migrants from Manus Island and Nauru to new detention centres.
She said people in the processing centres have been suffering for more than six years, stressing that more humane policies could, and should, be implemented.