The top US court has dismissed an appeal case by a British company claiming it was wrongfully excluded during South Korea's purchase of advanced US-made F-35 fighters, Seoul's arms procurement agency said Thursday.

The US Supreme Court dismissed the appeal Monday in a case that South Korea has argued is beyond the jurisdiction of US courts as the transaction was one between governments, according to the Defense Acquisition Program Administration (DAPA).

In December 2020, Blenheim Capital sued the South Korean government, Lockheed Martin, the F-35's manufacturer, and others, claiming it was excluded from the transaction as the broker of an offset program connected to the deal and sought US$500 million in damages, DAPA said.

High-cost military contracts between countries usually involve offset programs, where a buyer receives other goods or technologies in return for the deal. Seoul's F-35 purchase included an offset program involving a military satellite capable of integrating with the jets.

The court move came after the U.S. Justice Department called for dismissing the appeal last month, saying the transaction was not a commercial one and not within the reach of US courts, according to DAPA.

South Korea currently operates 39 F-35A fighters after purchasing 40 units from 2019 to 2022. One of the units was retired after being damaged by a bird strike in 2022. (Yonhap)