Seoul: South Korea has declined a proposal from the United States to conduct a trilateral air drill with Japan this month. The suggested timing of the drill coincided with Tokyo's annual commemoration of its territorial claim to a group of disputed islands, according to local media reports on Monday.

According to Anadolu Agency, last month, the United States pitched the idea of holding trilateral drills with South Korea and Japan in February. However, the proposed schedule clashed with South Korea's Lunar New Year holiday from February 15 to 18 and was just before Japan's "Takeshima Day" event. The event, which began in 2005, is an annual regional commemoration by Japan to assert its territorial claim to the Dokdo islets, known as Takeshima in Japan. This claim has been a longstanding source of tension between Tokyo and Seoul.

South Korea reacted to the situation by lodging a protest against Tokyo on Sunday after a senior Japanese official attended the "Takeshima Day" event. In response to the proposed air drills, South Korea suggested rescheduling them to a time well before Japan's regional event or conducting a bilateral aerial exercise with the United States after Japan's commemoration. However, Washington declined Seoul's offer earlier this month and instead informed South Korea of its intention to proceed with a solo aerial drill.

In a related development, South Korea also filed a protest with the US Forces Korea earlier this week following an unusual standoff with Chinese fighter jets during a training aircraft drill over the Yellow Sea. During an air exercise involving 10 F-16 fighter jets from the US Air Force, US and Chinese fighter jets engaged in a brief standoff over the Yellow Sea. The F-16 jets had flown to an area between the air defense identification zones of South Korea and China, prompting the Chinese military to dispatch its own fighter jets to the scene. Fortunately, no clash occurred during this incident.