President-elect Donald Trump piled on fresh criticism of the Pentagon’s most sophisticated aircraft on Thursday, suggesting that he might abandon the F-35 Joint Strike Fighter in favor of a cheaper plane because of the F-35’s high costs.

In a message on Twitter, Trump said that cost overruns in Lockheed Martin’s $400 billion program to develop the stealth jet had prompted him to ask Boeing, another major aircraft manufacturer, to “price-out a comparable F-18 Super Hornet.”

The Super Hornet is a fighter jet that began flying in the 1990s. While the F-35 has been declared combat-capable, the United States has yet to fly it in combat missions.

Trump has blasted the F-35 before, saying the cost is “out of control” and promising that his administration would find savings in military hardware purchases. His criticism of Bethesda-based Lockheed Martin and Chicago-based Boeing has roiled the defense industry and laid down a marker for a hard line from the White House in dealings with major players doing business with the government.

Even before Trump launched his public assault, the F-35, the Pentagon’s most expensive weapons program, has come in for widespread criticism for design flaws and spiraling costs. While the current price for the various F-35 variants is at least $100 million per plane, the company has said that it will fall to $85 million each in four or five years.

After President-elect Donald Trump took aim at Lockheed Martin's F-35 stealth jet project, two of the $100 million fighter jets landed in Israel. (Video: Reuters / Photo: AP)

This fall, Pentagon and officials from Lockheed Martin failed to agree on a mutually acceptable price for the latest batch of planes. And last month, Canada said it might buy Super Hornets until it decides whether to go ahead with planned F-35 purchases. A number of U.S. allies, including Israel, are buying F-35s.

While some lawmakers have criticized the program, the jet’s supply chain touches virtually every state, giving it many defenders in Congress. Lockheed Martin estimates the program accounts for 38,900 jobs in Texas alone, and close to 10,000 in Connecticut.

In an email, Lockheed Martin spokesman Bill Phelps declined to comment.

Addressing Trump’s comments earlier this week, Air Force Secretary Deborah James defended the F-35 program and said that costs had been coming down.

“I think any incoming president or any incoming leader is going to be asking questions,” James said at an event at the Atlantic Council, a Washington think tank. “But with time and as additional material is presented and briefings are had, the complexity of both of these programs come to the light. And so it’s not quite as easy as it might seem to get these costs down.”

Lockheed shares fell 2 percent in after-hours trading, wiping out about $1.5 billion in shareholder value, while Boeing rose 0.67 percent immediately following the president-elect’s tweet.

Trump has also assailed Boeing over the high cost of a new Air Force One plane in the works. Its chief executive later met with the president-elect and promised to give the U.S. government a break on the aircraft.

“We have committed to working with the president-elect and his administration to provide the best capability, deliverability and affordability across all Boeing products and services to meet our national security needs,” Boeing spokesman Todd Blecher said in a statement.

Loren Thompson, chief operating officer of the nonprofit Lexington Institute, said that Trump appeared to have decided to start negotiations before he had a thorough understanding of the F-35 program. “This certainly sets some sort of precedent because no Commander in Chief has ever done this before being inaugurated,” he said.

“Mr. Trump needs to understand all the costs of substituting one aircraft for the other,” Thompson said.

Carol Morello, Dan Lamothe and Steven Mufson contributed to this report.

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