ⓒYONHAP News

The nuclear-powered U.S. aircraft carrier, the USS Ronald Reagan, arrived in South Korean waters on Friday to participate in the first exercises involving a U.S. carrier in five years.

The carrier strike group docked at the Republic of Korea Fleet Command in the southeastern port city of Busan at 9:00 a.m., consisting of the USS Ronald Reagan, the Aegis-equipped USS Barry destroyer and the guided-missile cruiser, the USS Chancellorsville.

The three warships, along with the nuclear-powered USS Annapolis submarine, are expected to take part in joint drills conducted in the Korean Theater of Operations off the east coast later this month.

The training comes after the leaders of South Korea and the U.S. reaffirmed their commitment to deploy U.S. strategic assets to the Korean Peninsula back in May as a part of a reinforced deterrence against North Korea's evolving military threats.

Participating in South Korean naval exercises for the first time since 2017, the 97-thousand-ton Ronald Reagan is capable of carrying some five-thousand sailors and 90 aircraft, including F/A-18E Super Hornets and E-2D Hawkeye early warning and control aircraft.

The South Korean military said Saturday it had detected signs in North Korea that suggest the regime may be preparing to fire a submarine-launched ballistic missile (SLBM) from the Sinpo area on the east coast.

This move comes a day after the USS Ronald Reagan arrived in South Korea for a combined military exercise, and pundits say Pyongyang could be planning to fire a missile in protest. 

A South Korean military official said Saturday that the military was closely monitoring North Korea's SLBM-related facilities and activities, maintaining a thorough readiness posture.

The military reportedly detected possible signs of preparation for an SLBM test on Wednesday and Thursday, but has not unveiled details of what they are.

The eastern coastal city of Sinpo is home to the North's production, development and test facilities for SLBMs, with a ground test-launch site nearby.