North Korean leader Kim Jong Un urged senior military officials to strengthen frontline units and turn the southern border into an “impenetrable fortress,” according to state media on Monday.

Kim delivered the remarks during a meeting on Sunday with army division and brigade commanders, the Korean Central News Agency reported.

According to the report, Kim outlined plans to reinforce frontline and key military units from both military and technical perspectives as part of what he described as an important decision to prevent the outbreak of war on a broader scale.

The report added that the military’s strategic operations would be “renewed” and that a “major transformation” would take place in war deterrence efforts, without providing further details.

State media also said commanding officers at all military levels must continue strengthening their awareness of the “principal enemy,” in an apparent reference to South Korea.

Kim additionally discussed the ruling party’s regional defense policy aimed at reinforcing frontline units along the southern border and transforming the boundary line into a “strong defensive fortress.”