The U.S. Federal Aviation Administration (FAA) now recognizes and interacts with the airlines as one, American Airlines said on Wednesday.

The regulator granted the single certificate because the majority of the carriers' flight, maintenance and dispatch procedures are now identical.

The carriers will now focus on moving to a single reservation system and website, as well as combining their frontline employee workgroups, Chief Operating Officer Robert Isom said.

American Airlines, which transitioned to a single loyalty program for frequent fliers on March 28, said it expects to move to the single reservation system later this year.

American Airlines shares rose 1.7 percent to $48.30 in morning trading on the Nasdaq. Up to Tuesday's close, the stock had fallen 11 percent this year.

(Reporting By Jeffrey Dastin in New York and Sagarika Jaisinghani in Bengaluru)