FILE PHOTO: United Technologies logo is displayed on a screen at the post where it's stock is traded on the floor of the New York Stock Exchange (NYSE) in New York, U.S., September 5, 2017. REUTERS/Brendan McDermid

WASHINGTON (Reuters) - Pratt & Whitney, a unit of United Technologies Corp UTX.N, has been awarded a $2.2 billion U.S. defense contract for production of F135 propulsion systems, the Pentagon said on Monday.