An Australian lawyer says it's not viable for Canberra to consider re-opening its asylum seeker detention centre on Nauru.
The Australia federal government's policy of mandatory detention of unauthorised arrivals on Christmas Island is under increased pressure with the island near its capacity of 1900.
The opposition has suggested re-introducing elements of the former Howard Government's so called Pacific Solution in which asylum seekers were housed on Nauru or on Manus Island in Papua New Guinea.
But lawyer, Julian Burnside, says holding people offshore costs around five times more per day than it would in Australia itself and the opposition is on the wrong track to suggest re-opening camps such as Nauru.
"First of all its morally bankrupt. Second its unnecessary. Third, it would be absurdly expensive. Fourth, I suspect that it wouldn't work. I suspect that the government of Nauru would no longer tolerate being used as a warehouse for refugees because the government of Nauru now is rather better than the government of Nauru was in September 2001 when the Pacific solution was created."
Mr Burnside says any overflow of asylum seekers should be housed on mainland Australia.