The drills came a day after South Korea and Japan reported North Korea's launch of several short-range ballistic missiles into the sea, its first such missile test in about two months.

Kim guided the drills on Monday that were aimed at testing the "real war capabilities" of 600 millimetre multiple rocket launchers and improving the operators' combat morale and readiness posture, KCNA said.

Seoul's defence minister, Shin Won-sik, said at a news conference on Monday that if Pyongyang fires a large number of conventional missiles against the South, it would "constitute a war" and prompt strong retaliatory attacks.