STORY: The three-day drills took place in international waters off the Japanese island of Okinawa until Saturday, including air defense, anti-ship, anti-submarine, and maritime interdiction operations, South Korea's Joint Chiefs of Staff (JCS) said.
The USS Ronald Reagan, a 100,000-ton nuclear-powered aircraft carrier, joined the drills, alongside the guided-missile cruiser USS Antietam, the Aegis-equipped USS Benfold destroyer, and the Fleet replenishment oiler USNS Big Horn, the JCS said.
South Korea also sent the 14,500-ton Marado amphibious landing ship, the 7,600-ton Sejong the Great destroyer, and the 4,400-ton Munmu the Great destroyer, among others.
It was the allies' first joint military exercise since South Korea's President Yoon Suk-yeol took office last month, and their first bilateral exercises involving an aircraft carrier since November 2017.
The exercises came amid signs that North Korea is gearing up to conduct a nuclear test for the first time since 2017.