Australians travelling to Europe and the Middle East could be facing longer flight times and diverted flight routes following Iran's missile attacks onto US airbases in Iraq.

Key points: Qantas will no longer fly through Iran or Iraq airspace, which may lead to the suspension of the newly-launched Perth-London route

Qantas will no longer fly through Iran or Iraq airspace, which may lead to the suspension of the newly-launched Perth-London route Other airlines have also announced diversion of flights around Iran and Iraq

Other airlines have also announced diversion of flights around Iran and Iraq It comes after Iran launched missiles at US bases in Iraq following America's killing of a top Iranian general

Qantas has announced it will avoid airspace over Iran and Iraq until further notice, which may lead to the suspension of Qantas's direct Perth-London route, which was launched less than two years ago.

The airline said it was considering sending the flights leaving Australia through an Asian city to refuel, given the extra distance.

Direct flights from London to Perth would be able to continue thanks to prevailing wind conditions.

The 17-hour long-haul journey would be the only Qantas flight affected by the diversion.

Qantas said none of its planes were in the region when Tehran launched "tens" of surface-to-surface missiles at the Al-Assad and Erbil bases in response to America's killing of a top Iranian general.

Several other international carriers, including Emirates, Etihad, and Qatar Airways, offer indirect stopover flights from Australia that travel through the area.

Many have announced they would be diverting or cancelling flights in the wake of the heightened tensions.

Erbil airbase and Al Asad airbase were hit in the attacks. ( ABC News )

US Federal Aviation Administration bars carriers and pilots from airspace

Earlier on Wednesday, the Federal Aviation Administration (FAA) announced it was barring US pilots and carriers from flying in areas of Iraqi, Iranian and some Persian Gulf airspace.

Such restrictions are often precautionary in nature to prevent commercial aircraft from being confused for ones engaged in armed conflict.

Loading

Australia's Civil Aviation Safety Authority (CASA) does not have the same jurisdiction in Australia as the FAA does in the US and does not issue bans on carriers from flying in certain areas.

CASA said it would be up to individual airlines to assess whether or not to continue flying through the regions.

Major airlines divert routes

Singapore Airlines Ltd said after the attacks that all of its flights would be diverted from Iranian airspace.

Malaysia Airlines said it did not fly over Iraqi airspace and would re-route to avoid Iran as a result of the attack.

Taiwan's China Airlines said it would not fly over Iran or Iraq because of the tension.

Dubai-based Emirates and flydubai each cancelled a return flight to Baghdad on Wednesday after Iran's missile attack and said it would make further operational changes if required.

"We are carefully monitoring the developments and are in close contact with the relevant government authorities with regards to our flight operations, and will make further operational changes if required," Emirates said in a statement.

Qatar Airways said its flights to Iraq were operating normally.

Korean Air Lines Co Ltd and Thai Airways said they had been avoiding Iranian and Iraqi airspace before the attack on US troops.

Space to play or pause, M to mute, left and right arrows to seek, up and down arrows for volume. Watch Duration: 40 seconds 40 s Prime Minister says Australian personnel in Iraq are safe

Transport Canada said it was in close contact with the FAA and that Air Canada was altering its routes.

India's aviation regulator has not issued formal instructions to airlines yet but has held meetings with those concerned and advised them to remain vigilant and take precautions, an official said.

Carriers are increasingly taking steps to limit threats to their planes after Malaysia Airlines Flight MH17 was shot down in 2014 by a missile over Ukraine, killing all 298 people on board.

International aviation task force created

An international aviation team has been activated to support "effective coordination and communication" between airlines and countries as tensions mount.

The coordination team operated by the International Air Transport Association (IATA) and the International Civil Aviation Organisation was activated as a "standard precautionary measure", in the event that contingency measures are required by airlines, IATA said in a statement to Reuters.

The team brings together airlines, regulators and air navigation service providers to ensure any potential risks to aviation are shared quickly, an industry source familiar with the group said.

"Everyone's urging restraint," said the source, who spoke on condition of anonymity because of the sensitivity of the matter.

ABC/Reuters