Defence Industry Minister Christopher Pyne has played down reported weaknesses in Australia's anti-terrorism laws, even as Immigration Minister Peter Dutton called for greater powers to stop foreign fighters coming home.

Intelligence experts have warned the government of flaws in legislation designed to strip citizenship from dual nationals who leave Australia to fight with Islamic State in Iraq and Syria, News Corp reported on Friday.

Authorities cannot strip someone of their Australian citizenship without first proving the person is a citizen of another country, requiring the co-operation of the Iraqi and Syrian governments, who have so far refused.

Reports suggested there was "nothing" to stop about 100 terrorists coming back to Australia as the Islamic State weakens in the Levant and loses territory. But Mr Pyne dismissed the report as "a sensational beat-up".