Kim also highly appreciated the fact that the demonstration fire had been successful, the Korean Central News Agency reported.

On Tuesday, the South Korean Joint Chiefs of Staff said North Korea had twice launched unidentified projectiles into the Sea of Japan. Before that Pyongyang had already conducted three short-range missile tests within less than two weeks.

The United States and South Korea began their annual military exercises on Monday. The exercises were kept low-key after North Korea warned the drills could derail nuclear negotiations.