Progressive South Korean presidential candidate Lee Jae-myung on Wednesday urged his conservative opponent to retract his support for a “preemptive strike” in the event of a pending North Korean hypersonic missile attack, describing Yoon Suk-yeol’s comments as reckless and dangerous.

Yoon of the People Power Party (PPP) suggested the idea the previous day in response to a question about North Korea’s latest test of a hypersonic missile that could potentially thwart conventional missile defenses with its high speed and maneuverability.