DEFENSE DRILLS. South Korean, US and Japanese warships engage in maritime drills in the international waters of East Asia on this February 22, 2023 photo. The three countries have stepped up their efforts in deterrence against North Korean threats. (Yonhap file photo)

SEOUL – South Korea, the United States and Japan began a trilateral missile defense exercise in the international waters of the East Sea on Monday, Seoul's Navy said, amid stepped-up efforts to sharpen deterrence against North Korean threats.

The three nations have been reinforcing security coordination following Pyongyang's provocative acts, such as the launch of a purportedly solid-fuel intercontinental ballistic missile last Thursday.

The exercise featured three Aegis-equipped destroyers – the South's ROKS Yulgok Yi I, the US' USS Benfold and the Japan Maritime Self-Defense Force's JS Atago, according to the armed service.

It focused on practicing procedures to detect and track a computer-simulated ballistic missile target and share related information.

"This was an opportunity to strengthen security cooperation among the South, the US and Japan against the North's advancing nuclear and missile threats, and firm up our Navy's capabilities to respond to ballistic missile launches," a Navy official was quoted as saying.

The three countries last held such a three-way missile defense exercise in February.

During their senior-level defense dialogue, called the Defense Trilateral Talks, last week, they agreed to hold missile defense and anti-submarine exercises regularly to counter the North's threats. (Yonhap)