Australian air force personnel have completed their first operational missions in Iraq as part of efforts to combat Islamic State extremists.

Defence says a Wedgetail early warning control aircraft and refueller aircraft supported missions flown by US and other coalition forces on Wednesday.

The missions were conducted without incident and both planes have now returned safely to Australia’s support base in the United Arab Emirates.

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The Iraqi government is yet to make a specific request for Australia to take part in a specific combat operation, Foreign Minister Julie Bishop said.

Once that request comes – expected within days – the national security committee and then cabinet will have to consider it.

“We are being prudent and measured and cautious in relation to this matter,” Ms Bishop said.

Prime Minister Tony Abbott said the support missions would continue.

“We at this stage are not flying strike mission, but in coming days the government will be making further decisions,” he told reporters in Melbourne.

Ms Bishop insisted there was no “hold up” on Australia’s combat role.

“I expect that in the next few days we’ll have the appropriate clearances,” she said.