Budget airline Ryanair has been ordered to pay compensation to passengers stranded after the 2010 volcano eruption in Iceland, leaving the door open for a raft of claims, but also a potential increase in ticket prices.
The European Court of Justice ruled that airlines face an obligation to provide care if passengers are left stranded due to flight cancellations arising from "extraordinary circumstances".
That includes refreshments, meals, hotel accommodation and transport between the airport and place of accommodation, as well as communication costs.
The ruling comes after an Irish customer, who was stranded for a week during the Eyjafjallajokull volcano eruption, claimed costs from the airline.
Denise McDonagh was stranded in Faro, Portugal while waiting for a flight to Dublin for a week, during the ash cloud crisis. She was not provided with any care and demanded compensation of almost 1,130 euro (£970) to cover meals, refreshments, accommodation and transport.
The eruption left millions of passengers unable to return home because it was too dangerous to fly through the ash clouds The court recognised claims could have "substantial negative economic consequences" for airlines, but said a high level of protection must be afforded to passengers.
"The importance of that objective may justify even substantial negative economic consequences for certain economic operators," the court said. But airlines could pass on such costs in increased ticket prices.
"In addition, air carriers should, as experienced operators, foresee costs linked to the fulfilment of their obligation to provide care," the judgment said. "Furthermore, they may pass on the costs incurred as a result of that obligation to airline ticket prices."
The ruling comes after a judge at Stoke-on-Trent County Court awarded Staffordshire couple Jeff and Joyce Halsall 800 euro (£680) in compensation and legal costs after their Thomas Cook flight in October 2009 was delayed by a mechanical fault, according to the Daily Mail.
Ryanair has said it paid out 26.1 million euro (£22 million) to stranded passengers but it has refused many claims, citing their "excessive" cost. The court said passengers can only claim "reasonable" costs.