STOCKHOLM - Lufthansa could face "unlimited" compensation claims for the crash that killed 150 people in the French Alps and it would be difficult, even counterproductive, for the German carrier to try to avoid liability, experts said Friday.

Under a treaty governing deaths and injuries aboard international flights, airlines are required to compensate relatives of victims for proven damages of up to a limit currently set at about $157,000 - regardless of what caused the crash. But higher compensation is possible if a carrier is held liable.

"So more or less you will have unlimited financial damage," said Marco Abate, a German aviation lawyer.

To avoid liability, a carrier has to prove that the crash wasn't due to "negligence or other wrongful act" by its employees, according to Article 21 of the 1999 Montreal Convention.

That would be a difficult argument to make when a pilot intentionally crashes a plane into a mountain, and one that Lufthansa would likely avoid as it could further damage the brand, Abate said. Investigators say the copilot of Germanwings Flight 9525 locked himself into the cockpit and slammed the Airbus A320 into the Alps. Germanwings is a subsidiary of Lufthansa.

Lufthansa chief executive Carsten Spohr said Thursday that the airline would honor "international arrangements regulating liability." The company is offering immediate aid of up to $54,800 per passenger to victims' relatives. Those payments are separate from eventual compensation payments.

How much the airline ends up paying in compensation will depend on where claims are filed. The options in this case, a German flight en route from Barcelona to Düsseldorf, are many, said Dutch lawyer Sander de Lang. "For example, French law because that is where it ... crashed, German law because in most cases the passengers had return tickets to and from Germany. But some people may have bought tickets in Spain, then Spanish law could be appropriate," he said.

Damages are typically much lower in Europe than in the U.S., where in domestic air crashes, juries have awarded plaintiffs sometimes millions of dollars per passenger. The families of the three American victims could sue the airline in U.S. courts. Article 33 of the Montreal Convention states that a passenger's "principal and permanent residence" is used to determine jurisdiction for suits regarding passenger deaths or injuries.