The Australian Government is being called to explain why it is spending $AU3.5 million of taxpayers' money annually for each refugee it is detaining on Nauru.
New figures released to the federal parliament reveal large amounts of money still being spent on the detention of refugees and asylum seekers on the island.
The refugee population on Nauru is now just a tenth of what it was as the height of Australia's scheme to place people trying to reach the mainland illegally by boat on the island.
Refugee supporters hold placards as they gather in Sydney to mark the milestone of 200 days of continuous protests in the detention camp on the Pacific island of Nauru in 2016. Photo: AFP
But Canberra is still paying out what it was five years ago, despite numbers falling to about 100 refugees.
It is estimated the detention of each refugee is costing the Australian taxpayer $AU15,000 every day.
The opposition Labor Party's deputy leader in the Senate, Kristina Keneally, says prime minister Scott Morrison has to explain what is going on.
She says the Australian people deserve to know what is happening to their money.
Australian media has reported the government saying the hundreds of millions of dollars spent since 2012 on the camp have been well spent, saving boat people from drowning at sea.
In September the Government renewed a long-term commitment with Nauru to maintain the camps.
It has also said all future illegal arrivals by boat will be sent to Nauru, in the wake of a similar arrangement with Papua New Guinea being declared illegal by that country's Supreme Court.