South Korea is in the final stage of assembling a prototype of what would be the country's first indigenously developed fighter jet, which is expected to be unveiled in April, officials said Sunday.

South Korea has been working on the KF-X project since 2015 to develop a homegrown cutting-edge fighter aircraft to replace the Air Force's aging fleet of F-4 and F-5 jets.

In September last year, Korea Aerospace Industries Co. (KAI) got down to the final assembly of a prototype jet and is now in the final stage, according to officials of the Defense Acquisition Program Administration (DAPA).

The prototype is expected to be made public in a rollout event in around end-April, weeks ahead of schedule, they added.

The procurement agency is eyeing 2026 for the completion of development after ground and flight tests. Forty units are planned to be delivered to the Air Force by 2028 and another 80 units by 2032, the officials said.

The aircraft is designed to be able to fly at a maximum speed of Mach 1.81, with its flying range reaching 2,900 kilometers. It bears outward similarities to the fifth-generation F-35A, according to the KAI.

With a maximum payload of 7,700 kilograms, the fighter is capable of installing 10 pods for missiles and fuel barrels. It will be able to carry several types of air-to-air missiles, such as Germany's IRIS-T and European developer MBDA's active radar guided Meteor missiles, it added.

"KF-X is categorized as a '4.5' generation fighter jet. But the platform is designed to be converted into an advanced, fifth-generation one at any time," a DAPA official said. (Yonhap)