Pyongyang tested a new nuclear-armed underwater drone, state media reported, and North Korean leader Kim Jong-un warned that joint military exercises between South Korea and the United States should end.

During the test, North Korea's new drone yesterday moved underwater at a depth of 80 to 150 meters for more than 59 hours and detonated a non-nuclear payload near the country's east coast, North Korean media reported.

"This nuclear-powered underwater attack drone can be deployed to any coast and port or towed by a surface ship for operation," the KCNA report said, noting that Kim personally supervised the test.