South Korean military authorities say they were aware of most of what was unveiled by North Korean state media on Monday regarding the drills of its tactical nuclear weapons units. They added that South Korea's missile defense systems remain able to detect and intercept North Korean missiles. 

In a briefing on Tuesday, the Joint Chiefs of Staff spokesperson Kim Jun-rak also said that the North's firing of a submarine-launched ballistic missile from a reservoir is a desperate measure to try and evade South Korea's Kill Chain capabilities, as well as the surveillance capabilities of Seoul and Washington. 

Noting the potential implications of an SLBM launch from a reservoir, Kim said the military will thoroughly analyze the situation and maintain a firm readiness posture.

Regarding Pyongyang's claim that a large-scale exercise involving more than 150 fighter jets took place on Saturday, Kim said Seoul had been aware of the drill and that response measures in the event of a contingency had been in place.

The defense ministry's deputy spokesperson Moon Hong-sik also said the assault assets and launch delivery vehicles unveiled by the North can be detected and struck down by South Korea's missile defense system.

Moon said that while South Korea’s reconnaissance capabilities have reached an advanced level, the military is continuing to acquire more assets, including satellites and drones, to monitor all areas of North Korea.