Ms Bishop told the ABC's Insiders program on Sunday that the government was concerned that a number of Australians who were travelling through Lebanon to reach Syria were now moving from Syria into Iraq to join Sunni militants.

She said the government had cancelled several passports for Australians seeking to fight in Iraq, as it had done when it was reported that Australians were seeking to join or come back from fighting in Syria.

“We are receiving reports that they are also in Iraq where ISIS is fighting the Iraqi security forces and so we are doing what we can across government,” Ms Bishop said.

“It is a topic that is engaging the Australian government at every level.

“Our national security committee is discussing this matter and we are working out ways to ensure that Australians are safe from what I find to be a deeply disturbing development in our domestic security.”

Ms Bishop said she was in regular talks with her counterparts in Malaysia, South East Asia, Europe and the US about the issue.

“It's a global issue but we are particularly concerned with the reports of Australians who are heading off not only to train but to take leadership roles in radicalising others and of course the fear is that they will come back to Australia with these newfound abilities and talents in terrorism.”

But she again talked down the possibility of Australia contributing to greater military involvement in Iraq, beyond the small detachment of Australian soldiers that has been sent to guard the Australian embassy in Baghdad.

“I don't envisage that situation,” she said.

“Certainly the Iraqi Government has not requested support, has not requested Australia to provide any military support.

“The US has not requested us to do so.”

Australia is contributing $5 million in humanitarian aid to Iraq.