Cathay Pacific said it has cancelled 48 flights after discovering an engine glitch in one of its A350 aircraft.

The city's flag carrier said it identified an engine component failure in an A350 aircraft en route to Zurich on Monday. That forced the flight to return to Hong Kong.

"This component was the first of its type to suffer such failure on any A350 aircraft worldwide," Cathay said in a statement.

The carrier has since inspected all 48 of its A350 aircraft and found that some of the same components required replacement.

It said 48 flights operating through Tuesday were cancelled. Affected passengers have been informed and offered alternative travel arrangements.

“Each aircraft is undergoing a rigorous inspection. Upon completion, the aircraft cleared for operation will return to service, while those identified with technical issues will undergo further repair and maintenance work," Cathay's engineering director Keith Brown said.

"Meanwhile, we are liaising with the Hong Kong Civil Aviation Department and the aircraft and engine manufacturers.”