Australian warplanes are being deployed to the Middle East to join the US-led campaign of air strikes on jihadist targets in northern Iraq, Defence Minister David Johnston said on Monday.

"We will provide a number of military platforms, up to eight Super Hornet aircraft to participate in a US-led coalition in delivering air strikes," he told reporters in Baghdad after meeting Iraqi Prime Minister Haider al-Abadi.

Prime Minister Tony Abbott announced on September 14 that Australia would send fighter jets and forces to the United Arab Emirates as its contribution to the US-led military effort against the Islamic State (IS) jihadist group.

"We are in the process of deploying them to the Middle East," Johnston said Tuesday, adding however that more preparation work was needed before the Australian jets were brought into action.

"We are some distance from the start of that now, we need to deal with a few technical matters with respect to operations," said Johnston.

The deployment also includes an E-7 Wedgetail early warning and control aircraft and an aerial refuelling tanker aircraft, as well as special forces who will act as military advisers.

The announcement comes after Australian police last week foiled an alleged plot by IS jihadists to conduct "demonstration killings" in the country, including randomly beheading members of the public.

IS fighters are active in swathes of Iraq and Syria but Abbott has said Canberra had no plans to intervene in the latter country.

According to the Pentagon, US aircraft have carried out 178 air strikes against IS targets in Iraq since August 8. France has since joined the campaign and launched its own strikes.

During his meeting with Johnston, Abadi reaffirmed his "rejection of any ground intervention in Iraq," his office said.

- Returning jihadists -

Washington has repeatedly asserted that it would not deploy ground troops to the country in which its forces fought a bloody and costly war before withdrawing at the end of 2011.

Australia was one of the four countries -- together with the United States, the Britain and Poland -- that invaded Iraq in 2003 to topple Saddam Hussein.

Footage of the beheading of foreign hostages, mass executions of Syrians and Iraqis and the scale of the humanitarian disaster caused by IS has shocked public opinion.

There was particular revulsion in Australia last month over a picture of what is believed to be the young son of an Australian man holding the severed head of a Syrian soldier by the hair.

Thousands of foreigners have joined the ranks of IS, which declared a "caliphate" over parts of Iraq and Syria and is widely regarded as the most violent and powerful organisation in modern jihad.

Western countries in particular have voiced concern over the threat posed by returning jihadist.

The main suspect in a deadly attack on the Jewish museum in Brussels in May is a Frenchman who spent more than a year fighting in Syria.

Johnston said there are "approximately 65" Australians fighting with the jihadists in Syria.

Australia has announced tougher counter-terrorism measures to target its citizens who fight overseas due to fears that violent jihadist in Syria and Iraq will return home.

Australia's high-profile involvement in the US-led military effort gave it a prominent place in a statement IS posted Monday calling on Muslims to kill any citizen from a member country of the anti-jihadist coalition.