Japan will pay an estimated $10 billion (¥802 billion) for its order of 42 F-35 stealth jets at a cost of roughly $240 million (¥19.2 billion) per plane, the U.S. Defense Department reported to Congress, revealing price projections for the first time.

Tokyo has selected the F-35 Joint Strike Fighter produced by a U.S.-led consortium as its next-generation mainstay fighter over various other candidates, including the Eurofighter Typhoon that was aggressively promoted by a European group.

Japan is hoping to procure four F-35s by March 2017, and the Pentagon is expected to start mass producing them at domestic plants in 2019 at the earliest.

While the final, official sales price has yet to be disclosed, the Defense Ministry estimates the fuselage alone will cost around ¥8.9 billion. The sales price per unit includes training and other costs.

Defense Minister Naoki Tanaka has already said Tokyo may cancel the order if the jets' delivery is delayed or the price tag hiked.