US warns airliners travelling through Iranian airspace

The US aviation body has urged airliners to be cautious when travelling through Iranian airspace, as tensions between Tehran and Washington heighten. 

The warning comes after an American civil airliner was intercepted by fighter jets in December 2017, with fears of conflict in Syria and Iraq could also escalate in the region.

Federal Aviation Administration's updated guidance says "without seeming alarmist" airlines wishing to travel through Iranian airspace to be mindful of the escalating tensions between Tehran and Washington, and other regional conflicts.

"Although the reopening of Iraqi airspace in November last year has provided additional routing options... there is no perfect route in the region, and operators must consider their preference for Iraq vs Iran," Reuters reported the authority stating.

In December, the authority banned US airlines from travelling below 26,000 feet in Iraq due to conflict in the country.

The US State Department has also advised citizens against travel to Iran due to arbitrary arrests by Iranian authorities.

A number of US and British citizens - particularly dual nationals, have been detained by Iranian authorities - with critics of the Tehran regime saying they have been held for political leverage with Western powers.

Tensions between the two countries escalated when President Donald Trump tore up a nuclear agreement with Iran earlier this year.

Since then, the US has issued tough sanctions on Iran with further economic penalties against Tehran to be taken in November.

Many European airlines have cancelled flights to Tehran, due to the sanctions.

Agencies contributed to this story.