Seoul has notified Washington of its intention to purchase weapons systems worth US$800 million (S$1 billion) to be mounted on its new fleet of warplanes should a US fighter be picked for its 8.3-trillion-won ($7.4 billion) acquisition project.
The Defence Security Cooperation Agency, which handles Washington's foreign military sales, revealed Seoul's request to buy high-tech arms such as Advanced Medium-Range Air-to-Air Missiles, GBU-12 laser-guided bombs and GBU-39 bunker busters.
Last month, Seoul made a separate request to purchase Lockheed Martin's F-35 stealth fighter or Boeing's F-15 Silent Eagle.
The Eurofighter Typhoon of the European Aeronautic Defence and Space Company is another candidate in the competition, through which Seoul seeks to purchase 60 jets to replace its aging F-4 and F-5 jets. The winner is expected to be announced next month.
Observers said the US products would be at an advantage in the contest given Seoul considers interoperability with US forces and alliance-related factors. But EADS has made attractive offers, such as investing $2 billion in Korea's project to develop indigenous fighters.