ABC News Online revealed this morning that Nauru had established a new visa category, called an "Australian regional processing visa", with a cost of $3,000 for a three month period.
That contrasts with the $100 fee attached to a special purpose visa that is granted to a person "whom the principal immigration officer considers should be regarded as a refugee".
According to the regulations published on the Nauruan government's website, the regional processing visa can be extended so long as a new fee is paid "by or on behalf of the Commonwealth of Australia".
So far, 381 asylum seekers have been sent to the detention centre on Nauru as part of the Australian Government's new border protection policy.
Once the centre is fully operational, it is expected to hold 1,500 people.
Over a five-year period, the visa fees collected by the Nauruan government for 1,500 people would amount to $90 million.
A spokesman for Immigration Minister Chris Bowen says no money has been paid at this stage.
He says the visa fees have been factored in to the operating budget for Nauru, although he has not been able to say how much money is involved.
"The visa charges are the subject of discussions between Australia and Nauru, so it would not be appropriate to comment further," the spokesman said in a statement.
But a spokesman for the Government of Nauru has indicated the fee is unlikely to change.
"From the Nauru Government's perspective, that's the deal," the government's spokesman Rod Henshaw told ABC Radio Australia, in response to a question about whether the fee would be altered as part of ongoing talks.
"(The fee) was part of the original MOU (memorandum of understanding)... that there would be a visa fee.
"I don't know if there was a figure mentioned at that time, but it was arrived at and the Australian Government were notified of that."
Mr Henshaw says officials from both countries are still in negotiations about other aspects of the deal, including infrastructure and administrative costs.
Tax 'black hole'
The Opposition is demanding the Government explain what the long-term costs of the processing centre will be.
"Nothing would surprise me about this government," Opposition spokesman Scott Morrison told ABC News Online.
"I mean, their negotiating skills on asylum issues have already been proven to be deficient.
"They're not being upfront about what's happening on Nauru, they're not being transparent with the costs to the Australian people even as recently as the MYEFO (Mid-Year Economic and Fiscal Outlook) statement."
Greens Senator Sarah Hanson-Young believes the fees are an indication that Nauru does not want asylum seekers "dumped" there indefinitely, and says taxpayers will ultimately foot the bill.
"Really, is it in Australia's taxpayers' interest to be simply throwing money into a black hole just to keep the issue of refugees off the Government's political agenda?" she told BC NewsRadio.
"And, to that end, that's still not even working.
"We'll be obviously asking the Minister and the (Immigration) Department for clarification about how these fees will work."
According to the regulations, an asylum seeker on an Australian regional processing visa will be required to live in a dwelling identified by a "service provider" and remain there at all times.
Once the person has been formally declared to be a refugee and has passed a security check, they will be given more freedom to move around during the day, but will be subject to a curfew between the hours of 7pm and 7am.
The visa holder will not be allowed to work in Nauru except in a voluntary capacity.
Mr Bowen has been unavailable for interview because he is returning from Lebanon where he has been visiting refugee camps.
As part of the Government's commitment to increase Australia's humanitarian intake to 20,000 this financial year, Mr Bowen has announced the details of how many people will be accepted from different priority areas.
The program will target:
- Up to 2,000 African refugees, including people from the Democratic Republic of the Congo, Ethiopia, South Sudan and Eritrea
- Up to 3,800 Iraqi refugees from Syria, Turkey, Jordan and Lebanon
- Up to 2,000 Afghan refugees out of countries in the region
- 1,350 Burmese, Afghans, Iranians and other refugees living in Malaysia
- Up to 1,200 Bhutanese refugees out of Nepal
- Up to 800 Burmese refugees from Thailand
- Around 600 Afghan, Iraqi and Iranian refugees living in Indonesia
- Around 200 Burmese refugees in India
- Around 200 UNHCR referred caseloads outside these target groups
People claiming refugee status from within Australia and those who have arrived by boat will make up the bulk of the remaining 20,000 quota.