The South Korean government on Friday greenlit the initial mass production plan for KF-21 fighter jets on Friday, totaling 40 units, but with signing contracts set for the production of only 20 units this year.

The Defense Acquisition Program Administration emphasized the necessity of producing 40 KF-21 fighter jets, citing what it said was an urgent need to address the military capability shortfall resulting from the retirement of outdated F-4 and F-5 aircraft.

"This project is anticipated to prevent the vacuum in military capabilities resulting from aging long-term operational fighter jets and bolster the Air Force's foundational capabilities by acquiring a South Korean fighter jet capable of advanced combat and cooperative operations alongside advanced fighters," the APA said in a statement following a meeting on the matter.

The decision by the South Korean arms procurement agency regarding the size of the first batch for KF-21 mass production has sparked interest, particularly following the release of a feasibility study report by the state-run Korea Institute for Defense Analysis in November.

The report suggests decreasing the initial production quantity of KF-21 fighter jets from 40 to 20 units due to insufficient performance verification. This includes incomplete validation of the integration and connection between the AESA radar and air-to-air missiles mounted on the KF-21.

In light of KIDA's recommendation, DAPA has opted to contract 20 KF-21 units this June. The remaining 20 units will be contracted next year following further verification for performance.

"Validating the connectivity between the air-to-air missiles and AESA radar is crucial," a senior DAPA official said during a closed-door briefing on condition of anonymity.

"We aim to conclude the verification tests by June of this year, and following consultations with relevant agencies such as KIDA and the Ministry of Economy and Finance, we intend to finalize a contract for an additional production of 20 units by February next year," the official added.

Consequently, the initial plan to procure 40 units through initial production from 2026 to 2028, followed by an additional 80 units by 2032, allowing for the operation of a total of 120 KF-21s, can now proceed as originally envisioned.

The initial production of 40 units of KF-21, South Korea's first fully homegrown fighter jet, will require an investment of 7.92 trillion won ($5.92 billion) by 2028.