The UK Civil Aviation Authority (CAA) says it has started legal action against Ryanair (FR, Dublin Int'l) for refusing to pay compensation to passengers affected by a wave of strikes at the LCC during the Summer 2018 season.

According to European Union regulation EC261/2004, an airline can refuse the payment of fixed compensation ranging from EUR250 to EUR600 euros (USD285-680) if the delay or cancellation was caused by factors outside of the airline's control. In contrast to the CAA, Ryanair has long argued that strikes constitute an extraordinary circumstance.

The CAA said in a statement that Ryanair passengers affected by the strike had filed claims for compensation directly to the airline, but those had since been rejected. They were then able to escalate their complaints to AviationADR, a CAA-approved body, to provide alternative dispute resolution for passenger complaints.

"Ryanair has now informed the Civil Aviation Authority that it has terminated its agreement with AviationADR. As the Civil Aviation Authority said at the time of the industrial action, in its view, the strikes were not 'extraordinary circumstances' and were not exempt, meaning consumers should be compensated in accordance with Regulation EC261/2004," the regulator said adding that it had started legal action against the LCC on December 5.

The European Court of Justice has previously ruled that strikes, in general, are a normal part of the airline business and should not be considered extraordinary circumstances. Some national courts in the EU have, however, ruled otherwise.