U.S. approves military sale to South Korea for AIM-9X Sidewinder Block II missiles

The U.S. State Department has approved a potential Foreign Military Sale to South Korea of AIM-9X Sidewinder Block II air-to-air missiles and related support valued at an estimated $125 million, according to a government announcement.

Seoul’s request covers 103 AIM-9X Block II tactical missiles and 10 Block II tactical guidance units, along with an active optical target detector, training, training aids and devices, spare parts, weapon system support, and U.S. government and contractor engineering, technical and logistics services.

U.S. officials said the sale would advance American foreign policy and national security objectives by strengthening a key ally in the Indo-Pacific, enhancing South Korea’s air-defense capabilities, deterring regional aggression and ensuring interoperability with U.S. forces. The transfer would not alter the basic military balance in the region, and South Korea is expected to integrate the equipment without difficulty, the announcement said.

RTX Corporation of Arlington, Virginia, is the principal contractor. No offset arrangements are known at this time and would be defined in negotiations between the buyer and the company. The deal would not require additional U.S. government or contractor personnel to be assigned to South Korea.

The AIM-9X Block II is the latest variant of the U.S. short-range, infrared-guided Sidewinder, featuring an imaging seeker, thrust vectoring and a datalink that enables lock-on-after-launch, improving close-in air combat performance.

The State Department’s approval clears the way for congressional review and subsequent contract negotiations; it does not constitute a finalized sale.