WASHINGTON, Dec 28 (Reuters) - Lockheed Martin Corp and the U.S. Defense Department have reached an agreement freeing up preliminary funding for production of a sixth batch of F-35 Joint Strike Fighters, according to two sources familiar with the negotiations.
Details of the agreement will be worked out between the two sides in coming months, the sources said.
The Defense Department two weeks ago finalized an agreement with Lockheed for a fifth batch of planes, a $3.8 billion deal to buy 32 of the advanced, radar-evading aircraft.
At the time, company executives and defense officials said they expected to reach an agreement on early funding for the next group of planes by the end of the year.
The F-35 Joint Strike Fighter is the costliest weapons program in U.S. history.