A high-profile US naval strike group, led by the USS Carl Vinson, is staying near the Korean Peninsula on an open-ended mission, a defense official here said Tuesday.

The San Diego-based aircraft carrier arrived in Korean waters late last month as a show of force against North Korea.

The USS Carl Vinson, a US aircraft carrier, stages a joint exercise with South Korean warships. (Navy)
It is apparently supposed to be replaced by the USS Ronald Reagan aircraft carrier, which has its homeport in Japan and reportedly departed for routine patrol in the Asia-Pacific region after months of regular maintenance.

"Joint drills between South Korea and the US (involving the Vinson) are under way," Cdr. Jang Wook, a spokesman for the South Korean Navy, told reporters, adding the closing date has not yet been set.

He would not elaborate on whether the North's latest ballistic missile test has affected the schedule.

The Reagan successfully completed sea trials last week and embarked on its "regularly scheduled patrol" along with accompanying warships on Tuesday, according to the Stars & Stripes.

The Vinson's Asia patrol was "extended about a month amid a series of North Korean missile launches and speculation that the communist state could soon conduct a nuclear test," added the newspaper.

If true, the carrier is expected to be staying in the East Sea at least through the end of May. (Yonhap)