Iraqi army 'will fight back'

The Iraqi military remains "disjointed" but will rally to fight back against Islamic State if given help from Australian military advisers, Defence Minister David Johnston says.

Concerns about the ability of Iraq's military fightback against IS continue, with a flurry of reports in recent weeks of Iraqi units being overrun and slaughtered by Sunni rebels.

Australian Super Hornet strike jets have begun surveillance flights over northern Iraq from their base in the United Arab Emirates in preparation for bombing IS targets. The US-led coalition has ruled out sending combat troops to fight IS, meaning Iraqi forces will have to take the lead in pushing IS out of towns and cities.

But many military analysts question whether the Iraqi army has the skills or will for bloody house-to-house fighting.

Senator Johnston, who was in Baghdad last week, said there were "pockets" of highly trained and professional Iraqi security forces, but admitted many units were of low quality.

"Now they're a little bit disjointed," Senator Johnston said.

"They have been allowed to run down. In discussions with the Prime Minister in Iraq, I've told him this is a fight the Iraqis must fight." Reports say IS militants have control of key cities in Iraq's western province of Anbar and are now within artillery range of Baghdad and of the country's main airport.

Reports have emerged in recent weeks of whole garrisons of Iraqi soldiers being massacred by IS militants after being surrounded.

Iraqi army commanders are said to have botched efforts to resupply isolated units and in some cases accidentally parachuted supplies to IS fighters.

Australia has legal authority to carry out air strikes in Iraq, but is yet to get the paperwork it needs from the new Government in Baghdad to send military advisers into the country.

The Abbott Government has about 200 special forces soldiers - most of whom are Sydney-based commandos - on stand-by to go to Iraq to train and advise local troops.

Senator Johnston suggested Australian forces would be working with Iraqi counterinsurgency teams, possibly meaning Iraqi special forces.

When the US left Iraq in 2011, the country had 50 army brigades. Washington now says the country has only 26 "reliable" brigades.