The Freedom Edge exercise kicked off in international waters east and south of South Korea's southern island of Jeju, Yonhap News Agency reported, citing a statement from the country's Joint Chiefs of Staff (JCS).
The drill began as scheduled despite the administration of US President Donald Trump shortening the bilateral Ulchi Freedom Shield exercise with South Korea last month in an effort to encourage North Korea to return to talks.
"The three nations will leverage the drills to enhance operational capabilities and joint response capabilities across multiple domains, including maritime, air and cyber, while maintaining a robust and stable cooperative relationship," the JCS statement said.
The drills will involve major maritime and air assets from the armed forces of the three countries, with a joint exercise control group overseeing the operations for their systematic and safe execution, Anadolu Agency (AA) reported.
The Korean military said the joint drills are aimed at enhancing deterrence and response capabilities against North Korean nuclear and missile threats while safeguarding regional peace and stability.
The three countries will deploy six Aegis-equipped destroyers along with maritime patrol aircraft, fighter jets and refueling tanker aircraft, the report said, citing sources familiar with the matter.
The South Korean Navy is deploying the 7,600-ton ROKS Yulgok Yi I and ROKS Seoae Ryu Seong-ryong destroyers, said the sources.
Japan's Joint Staff of the Self-Defense Forces said last month that it will deploy the 7,700-ton Atago and 5,100-ton Asahi destroyers, P-1 maritime patrol aircraft, SH-60K helicopters and F-15 fighter jets.
The US Navy announced on social media last week the arrival of its 6,900-ton Arleigh Burke-class USS Benfold at a port in South Korea's southern city of Busan in a possible sign that it is joining the trilateral drills.
No US aircraft carrier is expected to participate in Freedom Edge given the ongoing US war against Iran, according to sources.
MNA