An Austrian court referred the case to the Court of Justice of the European Union, in which a passenger sought to claim compensation from Austrian Airlines.

The passenger arrived with a delay of more than seven hours from Romania to Austria after the aircraft the traveller was supposed to take was hit by lightning and had to be replaced.

Lightning "constitutes an extraordinary circumstance which may relieve the airline of the obligation to pay compensation... where it leads to mandatory safety inspections," the court said in a statement on the ruling.

It said it was up to the Austrian court to assess if the airline took "all reasonable measures" to avoid the extraordinary circumstances.

In 2017, the court classified a collision with a bird as "extraordinary circumstance".