About 200 commandos are in the Middle East waiting to join the fight against Islamic State, but they have been told they cannot enter Iraq without valid visas.

The Foreign Affairs Minister, Julie Bishop, was asked on Wednesday whether the troops were yet in Iraq and she declined to answer because of operational secrecy: "One doesn't flag what we intend to do to the enemy."

However, an informed source said the obstacle was not the enemy but the Iraqi government's excruciating inefficiency. Australian officials have been told it will take another week or two for visas to be granted.

Ms Bishop struck an agreement with Iraq on a legal framework for the deployment 10 days ago.

The troops have been waiting for at least a month and some have been waiting for two months. "We are just going through the administration to comply with the legal framework," a government source said.

A person knowledgeable about the matter said the Iraqi government's slowness was explained by political caution in allowing foreign troops to be seen on the ground.

Prime Minister Tony Abbott six weeks ago announced a preparatory positioning of forces in the region. This made Australia the first country to commit troops to the international effort.

He announced a formal cabinet decision to commit the commandos to combat on October 3.

The forces are waiting in the Al Minhad air base in the United Arab Emirates, 1700 kilometres from the fighting in Iraq.

The Australian government has repeatedly said in the past week that the final details of the deployment are still being worked out, citing only "administrative" reasons.

Iraq's ambassador in Canberra, Mouayed Saleh, could not be reached for comment on the issue on Wednesday night.

Iraq's Foreign Minister, Ibrahim al-Jaafari reportedly said earlier this month that Baghdad was "absolutely against foreign military bases and the presence of foreign military forces".

"Yes, we did ask for help, but it concerned air cover," he said. "The question of sending troops in was discussed several times and we were very frank and stated clearly that we are completely against the deployment of foreign troops on our territory, as it can cause justifiable fears and concerns among the Iraqi population."

The Australian soldiers largely from the elite Holsworthy-based 2nd Commando Regiment are expected to be partnered with an elite brigade of Iraqi special operations forces to help them battle against Islamic State militants.

Chief of the Defence Force Mark Binskin said earlier this month that the troops would "partner with like organisations" in their role advising and assisting local forces.

Most military analysts believe the battle against the Islamic State will not be won from the air alone and will require a massive effort by Iraqi forces on the ground and Kurdish Peshmerga forces. But the Iraqi forces, in particular, are not effective on their own and need support from international troops.

Australian special forces are world-renowned particuarly for their work in Afghanistan, where they did similar "advise and assist" work with local troops in fighting the Taliban.

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