A nuclear-powered U.S. submarine has arrived in South Korea to participate in an annual joint military drill this week, a naval officer here said Monday.

The USS Olympia (SSN-717), a Los Angeles-class submarine, carrying some 120 sailors, arrived in the southern port city of Jinhae, 410 kilometers south of Seoul, on Friday, to attend the joint Seoul-Washington three-day naval drill starting Thursday, the naval officer said, requesting anonymity.

"The submarine will join a South Korean fleet to launch the drill focusing on detecting enemies' submarines and surface vessels in waters near the Korean Peninsula in order to boost interoperability between the two nations and to check joint readiness," the officer said.

"It is not unusual for a nuclear-powered submarine from the U.S. to come here for the drill. Last year, the USS Colombia was here and took part in the annual Seoul-Washington exercise of Foal Eagle," he added.

The 7,000-ton submarine Olympia, equipped with Tomahawk land attack missiles and without any nuclear missiles, was forward deployed from Pearl Harbor at the invitation of the South Korean Navy.

Confirming the submarine's arrival here "as part of a routine visit," Lt. Arlo Abrahamson, spokesman for US Naval Forces Korea, said in a brief email statement that it "is currently on a regularly scheduled deployment to the Indo-Asia-Pacific region," without further elaboration.

The planned drill comes at a time when North Korea has called on Seoul and Washington to stop their joint military drills, claiming they are a rehearsal for a northward invasion, while the allies vow to carry them out as scheduled as they are defensive in nature.

It also took part in the ceremony marking the establishment of South Korea's Submarine Force Command in the port city on Monday, the officer said.

Speaking at the ceremony, South Korean Defense Minister Han Min-koo stressed the importance of boosting submarine capabilities, saying the new command "should play the key role in national defense to be the basis for the further development of the naval operations concept."

The South Korean Navy inaugurated the submarine command a day earlier as part of efforts to bolster its underwater capabilities and combat readiness against North Korea. (Yonhap)