Insurers breathed a sigh of relief this week after a landmark Court of Appeal ruling thwarted thousands of potential claims against airlines.

The ruling means relatives of airline passengers who have died from deep vein thrombosis (DVT) will be unable to claim compensation from airlines.

Three appeal judges upheld a decision made last year, which found that airlines were not liable. The judges' based their decision on the 1929 Warsaw Convention, which states that airlines are liable for claims only if injury was caused by an accident.

Sean Gates, senior partner at Beaumont & Son, which acted for the airlines, said: "It is a comprehensive judgment, which reiterates that claims against airlines are only allowed if an injury was caused by an accident. And as DVT is not caused by accidents, there can be no liability."

The International Underwriting Association (IUA), whose members insure airlines, welcomed the ruling. IUA operations director, Dave Matcham said: "This decision since it provides much needed certainty for the future."