By Doug Cameron

The civilian head of the U.S. Air Force said Monday that the incoming administration may find it tougher than they expected to bring down the cost of big military programs such as the F-35 combat jet.

President-elect Donald Trump has criticized the cost of the F-35 program, led by Lockheed Martin Corp., as well as the replacement for the Air Force One fleet being developed by Boeing Co. in a series of tweets and speeches over the past 10 days.

"It's not quite as easy as it seems to get these costs down," Air Force Secretary Deborah Lee James said during an event organized by the Atlantic Council.

Ms. James said she and other Pentagon leaders had briefed members of the transition team in recent weeks, and said its understanding of Air Force requirements and the complexity of the buying process would continue to develop. She added that some of the team were still in the process of securing the security clearances needed to fully assess programs.

The former congressional staffer and defense company executive pointed to existing efforts to cut the cost of the F-35, and said she was undecided as to whether Mr. Trump's comments would help bring down costs.

"Time will tell," she said of the tweets' impact. "It's good to have a focus on cost-saving measures."

Pentagon officials are due to hold a briefing on the F-35 program later Monday.

Some defense analysts said they didn't expect Mr. Trump's interventions to have a long-term impact on companies' earnings,even though the shares of some fell sharply last week in their wake.

"We don't think that the F-35 contracts will be rewritten, that [Lockheed] and its subcontractors will be mandated to accept lower margins, nor do we expect the program to be canceled," Richard Safran at Buckingham Research said in a client note.

Separately, Ms. James said existing restrictions on Pentagon staff working for industry were already "pretty strong," noting that she would be subjected to a two-year ban on working for military contractors when she leaves office.

Mr. Trump said at a rally last week that some Pentagon staff should have a lifetime ban on later working for industry.

Some staff directly involved in buying decisions already face such a lifetime ban, said Ms. James, a former executive at Science Applications International Corp.

Write to Doug Cameron at doug.cameron@wsj.com

(END) Dow Jones Newswires

December 19, 2016 12:48ET (17:48 GMT)

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