April 1 (Reuters) - American Airlines and online travel agency Orbitz Worldwide Inc, which have been locked in a years-long dispute over travel distribution costs and methods, on Monday said they have reached an agreement resolving the litigation between them. The companies declined to comment on details of the settlement agreement, which must be reviewed and approved by the U.S. bankruptcy court presiding over American parent AMR Corp's Chapter 11 case. American had sued Orbitz in April 2011, saying the online agency and airfare data provider Travelport, which owns a 48 percent share in Orbitz, made American's fares look higher than they were to consumers. American, which announced an agreement in February to merge with US Airways Group and form the world's largest air carrier, had stopped listing its fares on Orbitz in 2010 after the agency refused to adopt American's new technology that would let consumers price their trips based on other factors besides just fares. The carrier had resumed posting its fares on Orbitz.com in June 2011. Last month, Travelport and American announced that they had settled their antitrust lawsuit and signed a new global distribution agreement. Last year, American also reached a litigation settlement with flight reservations company Sabre Holdings Corp. The suit is American Airlines Inc. vs. Travelport Limited, a foreign corporation, and Travelport, LP, and Orbitz Worldwide, LLC No. 4:11-cv-00244-Y in United States District Court for the Northern District Of Texas Fort Worth Division.