The coalition is pushing to beef up proposed laws to strip dual Australian citizens of their citizenship if they're convicted of terrorism and espionage offences.
The legislation has passed the lower house and is before the Senate, where the opposition is moving to amend it.
Opposition Leader Peter Dutton wrote to the prime minister on Thursday outlining a number of other criminal offences that should receive the same treatment.
They include slavery offences, child sex offences outside Australia, torture, training with foreign militaries and advocating terrorism or genocide.
The letter, seen by AAP, says the "egregious offences are fundamentally inconsistent with Australia's values".
"The coalition's position is that in many circumstances these types of offences will constitute a repudiation of Australia and the Australian people," the letter states.
Shadow attorney-general Michaelia Cash chastised the government for failing to include historical cases with any application for someone to lose their citizenship needing to be made at the time of sentencing.
Senator Cash singled out Algerian-born convicted terrorist Abdul Nacer Benbrika, whose Australian citizenship was restored by the High Court earlier this year.
He is due to be released in the coming weeks with enhanced supervision in place.
"Australia's most serious ever convicted terrorist ... will remain an Australian citizen and that means a whole lot of options are taken off the table like deportation," Senator Cash told parliament.
The new laws patch up previous citizenship stripping powers after the High Court struck them out as unconstitutional, ruling only a court could punish criminal guilt, not a minister.
The minister would have to apply to the court after a person was convicted in order for someone's citizenship to be stripped under the new legislation.
The measure can only happen to dual citizens, as a person cannot be made stateless.
The Greens said there was no evidence the laws made Australians safer.
"What this does is create two different classes of people in this country that are treated differently under the law," Greens senator Nick McKim said.
Constitutional law expert George Williams has expressed the same doubts, saying stripping citizenship hasn't been proven to abate the risk of terrorism or to safety.
