Last month, the United Nations demanded that all states make it a serious criminal offence for their citizens to travel abroad to fight with militant groups, or to recruit and fund others to do so, in a move sparked by the rise of Islamic State.
Security analysts have put the number of foreign fighters in Iraq and Syria, travelling from scores of countries around the world, in the thousands.
Australian Prime Minister Tony Abbott told parliament at least 70 Australians were fighting in Iraq and Syria backed by about 100 Australia-based "facilitators".
The government had cancelled the passports of about 70 people, Abbott said.
"It's to protect other countries who shouldn't have to host Australians intent on mayhem, and it's to protect us, Madam Speaker, because Australians do have a right to come back to this country, and the last thing we should want is people on our streets who have been radicalized and brutalized by participation in terrorist activities overseas," Abbott said.
Australia is on high alert for attacks by radicalized Muslims or by home-grown militants returning from fighting in the Middle East, having raised its threat level to high and undertaken a series of high-profile raids in major cities.
The government, which recently warned that the balance between freedom and security "may have to shift", is also introducing controversial data retention laws it says are needed to tackle security and criminal threats.
Critics say the data laws go too far in compromising privacy, will be too costly and could open journalists and whistleblowers to hefty prison sentences. REUTERS