Multi-pronged effort vital to beat IS: PM

Prime Minister Tony Abbott says a range of measures aside from military action will be needed to disrupt the threat posed by Islamic State extremists in Iraq.

US President Barack Obama will make a speech on Wednesday (US time) to lay out his plan to deal with and "ultimately" defeat IS militants, although he continues to say the US won't be waging another ground war in Iraq.

Foreign Minister Julie Bishop has cast doubt on whether IS, also known as ISIS and ISIL, can be destroyed.

"I think that's impossible," she told Fairfax Media, warning the group had the potential to become like al-Qaeda. "Have we destroyed al-Qaeda?"

Mr Abbott appeared to back his minister on Monday, telling reporters Australia's role in an international coalition aimed to "protect people from ISIL, to disrupt and ultimately degrade what ISIL can do".

He stopped short of predicting a military defeat.

"There are a range of measures that will be needed to tackle the ISIL movement, and the military component is only a part of it," Mr Abbott said.

Other components include a broad-based government in Iraq, strong domestic security measures and working with like-minded countries in the Middle East , as well as reinforcing the notion of "Team Australia" among young Muslims at home.

The prime minister said no specific request had been made for an enhanced Australian military role in Iraq.

"We are continuing to talk to our partners and allies about how Australia might be able to contribute, whether we should help with some air capability, whether we should help with some military advisers," he said.

An Australian military plane has completed the airlift of a third shipment of weapons to Kurdish fighters in northern Iraq.

Defence says the Globemaster aircraft delivered without incident 50 tonnes of small arms and ammunition to Erbil on Sunday.

Iraq's parliament due on Monday to meet to vote on a new government in a key moment for the country, which is battling to regain territory from jihadist-led militants.

If a government is not agreed, it will mean a return to the start of the contentious process, leaving Iraq rudderless at a time of crisis.