South Korea can develop four key technologies that the United States has refused to transfer to Seoul for its fighter jet development project, the top security official said Friday.

The four technologies are something that "we can develop on our own," National Security Adviser Kim Kwan-jin said in a parliamentary session.

One of the four technologies is related to linking active electronically scanned array radars into fighters' mission computers, a critical element for manufacturing fighters with stealth capacities.

U.S. defense giant Lockheed Martin initially proposed to transfer a total of 25 technologies to South Korea under an offset deal linked to Seoul's purchase of 40 F-35 Lightning II fighters.

The 18 trillion-won ($16 billion) project is to replace 120 aging units of the Air Force's combat planes with locally manufactured ones starting in 2025.

In April, the U.S. State Department denied export licenses on four of the technologies. Last week, the U.S. defense chief rejected the request for reconsideration of the U.S. decision by his South Korean counterpart. (Yonhap)