South Korea's top military officer held talks with the new commander of the U.S. Pacific Fleet on Thursday on ways to boost the allies' combined defense readiness, the Joint Chiefs of Staff (JCS) said.

JCS Chairman Adm. Kim Myung-soo met US Adm. Stephen Koehler at the headquarters of the Navy's Fleet Command in Busan, 320 kilometers southeast of Seoul, according to the JCS.

The two admirals were briefed on naval operations at the unit's command center and held talks on ways to strengthen the combined defense posture, it said.

The US Naval Forces Korea, which operates under the US Pacific Fleet in Hawaii, is headquartered within the naval base in Busan.

Koehler, who took office earlier this month, is said to have also met Chief of Naval Operations Adm. Yang Yong-mo in Seoul on Wednesday. It marks Koehler's first visit to the country in his new role.

Separately, Kim visited the city hall of Ulsan, just north of Busan, earlier Thursday to inspect the ongoing Hwarang defense exercise, which began earlier this week.

The regular exercise between the military, local governments, police and rescue authorities is designed to boost readiness against North Korean military threats.

This year's Hwarang drills will focus on practicing management and response procedures after a North Korean nuclear or weapons of mass destruction attack for the first time. (Yonhap)