North Korea’s top military officials said ahead of a major parade they would expand and intensify military exercises to ensure combat readiness, North Korean state media reported on Tuesday.

The promise at Monday’s meeting, chaired by leader Kim Jong Un, comes after the United States and South Korea said they would hold joint discussion-based exercises to address nuclear threats, as featured at C4Defence last week.

The joint exercise, held for the first time this year, comes a day after US Secretary of Defense Lloyd Austin and his South Korean counterpart pledged to increase security cooperation against the nuclear-armed and increasingly aggressive North. The North Korean Foreign Minister said that the move to increase the joint exercises crossed the “red line”. On Monday, South Korea’s Ministry of Defense announced that a North Korean balloon had crossed its airspace over the weekend but concluded that it did not pose a threat.

Top officials of North Korea think Monday’s meeting was aimed at emphasizing the country’s readiness for real war and to counter upcoming joint military exercises between South Korea and the United States.

“North Korean operational and combat training implies the possibility of future military action in the name of war preparation,” said Hong Min, a researcher at the Korea National Unification Institute.

Kim Jong Un also said that his country should “massively increase its military strength” by 2023 in response to what North Korea calls hostility to the United States and South Korea.