Returning IS won't threaten safety

Some 110 Australians are fighting with terror group Islamic State but the federal government expects a much smaller number will seek to return home.

Justice Minister Michael Keenan said there was a good chance a significant number would be killed in fighting for Mosul and Raqqa, some dual nationals have lost their Australian citizenship while others won't want to return.

"We will make sure that anybody who returns from the conflict zone doesn't pose a threat to the Australian community. We are not going to allow them to threaten our safety," he told reporters in Canberra on Thursday.