North Korea leader Kim Jong Un on Wednesday ordered heightened war preparations two days after the U.S. and South Korea began their annual Freedom Shield exercise to strengthen deterrence against Pyongyang's nuclear and missile threats.

During a visit to a western operational training base, Kim called for intensifying "practical actual war drills," The Korea Times reported Thursday, citing the Korean Central News Agency (KCNA), the north's state-run media outlet. Kim inspected facilities at the base and guided maneuvers of military units.

On Tuesday, North Korea's Ministry of National Defense issued a statement denouncing the joint military exercise between the U.S. and South Korea, saying the countries will "pay a dear price."

The Freedom Sheild exercise, which will run for 11 days, comes as North Korea has ramped up weapons tests in recent months by launching cruise missiles from land and sea, and firing artillery near the western sea border.

During his visit, Kim also instructed the military to beef up drills to improve its combat capabilities to fight its enemies with "overwhelming force," the KCNA said in an English-language dispatch, according to the Times.

"He set forth the important tasks for intensifying the practical actual-war drills, ensuring victory in a war," the KCNA said.

In its statement, North Korea's Ministry of National Defense denounced "the reckless military drills of the U.S. and [South Korea] for getting more undisguised in their military threat to a sovereign state and attempt for invading it," and said it "severely warns them to stop the moves further causing provocation and instability."

"The armed forces of [North Korea] will continue to watch the adventurist acts of the enemies and conduct responsible military activities to strongly control the unstable security environment on the Korean peninsula," the ministry said.

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