A man freed from immigration detention after a landmark court decision will be placed under strict surveillance, with hundreds of others waiting to see what the ruling will mean for them.
The High Court has overturned a ruling allowing unsuccessful asylum seekers to be held in indefinite detention.
At least 92 detainees who can't return to their original country could be freed and another 340 in long-term detention could join them, the court was told.
Advocates are calling for every stateless person held in detention to have their case reviewed, although federal cabinet minister Murray Watt said no immediate action would be taken.
"The High Court has not published its reasons for the decision yet … we will obviously be obtaining the advice of the solicitor-general as to the implications of that decision for the other people who it may affect," he told parliament on Thursday.
The High Court plaintiff - a Rohingya man from Myanmar - was released after the ruling.
He faced the prospect of detention for life because no country would resettle him due to a criminal conviction for sexual intercourse with a 10-year-old.
Coalition members raised the risk to the community of releasing detainees locked up based on character grounds.
Foreign Minister Penny Wong said the plaintiff had been placed on strict visa conditions including reporting requirements.
"This is obviously a judgment that has significant implications," she said.
"This government will continue to work with authorities in our response to this decision to ensure community safety is upheld."
Refugee Council of Australia chief executive Paul Power said urgent action was needed to ensure no one else was illegally held.
"Indefinite detention has always been morally wrong and unlawful under international human rights law," he said in a statement.
"It is time now for the immigration minister to urgently review the cases of all those detained and work towards ending the policy of mandatory indefinite detention."
The Asylum Seeker Resource Centre pointed out Australia held immigration detainees for an average of 708 days, with 124 people detained for more than five years.
Greens senator Nick McKim queried what legal advice the government was waiting on to release detainees.
"What part of the words 'High Court of Australia' do you not understand?" he asked the Labor government.
"Have you got an argument with the High Court of Australia ruling and if not, why are you not getting to work now and ensuring all people within the scope of that ruling are freed?"