Telecomunicaciones y tecnología
No more big cash infusions for F-35 cost overruns: Air Force
He said that meant that any additional bills or cost overruns on the program could lead to a reduction in the total number of "tails" - or planes to be ordered.
Donley said he expected Lockheed and the government to "eventually" bridge their differences and reach an agreement on a fifth batch of F-35 production planes.
Those negotiations have been under way since December 2011.
(Reporting by Andrea Shalal-Esa; Editing by Gary Hill)