North Korean leader Kim Jong Un called for greater war fighting capabilities against the United States and South Korea, state media reported Thursday, after his defense ministry vowed to respond to the ongoing South Korean-U.S. military drills that it views as an invasion rehearsal.

During a visit to a western operational training base on Wednesday, Kim said the military must “steadily intensify the actual war drills aimed at rapidly improving its combat capabilities for perfect war preparedness,” the official Korean Central News Agency said. Kim said the heightened readiness is required to “contain the constant threat of the enemies with overwhelming force,” KCNA said.