The government needs "the modern form of banishment" to deal with Australians fighting for terrorist groups overseas, including sole Australian nationals, Prime Minister Tony Abbott says.
Mr Abbott says about half the Australians who have gone abroad to fight with the Daesh death cult as he calls it, or Islamic State, are dual nationals but the other half are sole Australian citizens.
Asked about suspending the citizenship rights of sole Australian nationals,he said the government would not do anything that was in any way contrary to the rule of law.
"One thing that we will never do is render people stateless," he told reporters in Melbourne on Saturday.
"But we are facing an absolutely unprecedented situation."
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He said the legislation currently before parliament to strip the citizenship of dual nationals fighting with terrorist groups overseas included provision for judicial review.
"The legislation that is before the parliament now obviously gives us ways of saying to dual nationals 'you're never coming back'.
"We need ways of dealing with those who are not dual nationals.
"Just as going abroad to fight with the death cult is the modern form of treason, perhaps to deal with it we need the modern form of banishment."
Immigration Minister Peter Dutton said the government was considering options relating to suspending the citizenship of 60 sole Australian nationals fighting in the Middle East but would not go into further detail.
"We want to make sure that we can protect the Australian people as best we can and if people have committed a criminal offence they will face the full force of the Australian criminal law," he told reporters.
He would not say what rights could be suspended.
Australia will block the return of dual citizens suspected of terrorism, based on security advice, and deport court-convicted terrorists under new national security laws. It is even looking at making the laws retrospective, meaning terrorists in jail could be deported after serving their sentence, but Mr Dutton said he did not have an update on this from the citizenship committee.
