This would be a significant development for both sides. Korea has to date only concluded a couple of FTAs (with Chile and Singapore), while this would be the US’ biggest FTA since NAFTA. The negotiations were reportedly arduous, with numerous domestic opponents on both sides. According to preliminary reports, rice has been entirely excluded from the FTA, Korea would resume beef imports (pending a favorable ruling by the WHO), and tariffs on vehicles under 3000cc would be eliminated with immediate effect.
The fate of the FTA remains up in the air, however. With presidential and parliamentary elections coming up, a promise to scuttle the ratification of the FTA would be an easy way to win the votes of the anti-US sectors in Korea. A similar fate could await the FTA in the US, where the automobile industry would feel particularly threatened by the tariff elimination.
Japan would likely watch forthcoming developments, particularly on the US side, with great interest. Recent strains in US-Korea and Japan-Korea relations have perhaps led to the impression that Korea is moving further away from its alliance with the US, in favor of closer ties with China. The successful approval of the US-Korea FTA would hopefully re-energize the relationship beyond a mere military alliance. However, the successful ratification of the FTA would probably also lead to pressure for Japan to open negotiations with the US. And would Japan really want an FTA with US, with all the attendant tariff reductions an FTA necessarily entails? It would perhaps not be too forward to suggest that Japan would hope that the FTA meets an unfortunate death in the US Congress, providing it with a convenient way to delay any progress on the issue.