"North Korea fired an unspecified ballistic missile toward the East Sea," Yonhap reported, quoting the Joint Chiefs of Staff, referring to the body of water also known as the Sea of Japan.

It comes after South Korea and the United States conducted large-scale annual joint military exercises, with double the number of troops participating compared to 2023.

Pyongyang last week warned that Seoul and Washington would pay a "dear price" over the Freedom Shield drills, and later announced that Kim had guided an artillery unit it says was capable of striking the South Korean capital.

Monday's apparent ballistic missile test is the North's second this year, after Pyongyang launched one tipped with a manoeuvrable hypersonic warhead on January 14.