Of the aircraft, 106 are destined for the US military: 64 F-35As for the Air Force, 26 F-35Bs for the Marines, and 16 F-35Cs for the Navy, while the rest are destined for foreign customers, the department said in a statement.

A major Pentagon supplier, Lockheed Martin will receive a $6 billion advance for the order, due to be completed in March 2023. Most of the work on the jets will be performed in the US, with some will be carried out in countries including Britain and Italy.

Launched in the early 1990s, the F-35 program is considered the most expensive weapons system in US history, with an estimated cost of some $400 billion and a goal to produce 2,500 aircraft in the coming years.

Once servicing and maintenance costs for the F-35 are factored in over the aircraft's lifespan through 2070, overall program costs are expected to rise to $1.5 trillion.

According to Pentagon figures from early October, 320 F-35s have been delivered worldwide, including 245 in the US.

The Pentagon also announced it ordered eight MH-60R helicopters from Lockheed Martin for $382 million.

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LOCKHEED MARTIN