North Korean leader Kim Jong Un said a U.S.-South Korea joint military exercise could "ignite a war" and called for the rapid expansion of Pyongyang's nuclear capabilities.

Kim Yo Jong, a senior official on the State Affairs Commission, called South Korean President Lee Jae-myung’s push for improved ties a “pipe dream,” according to a statement published by the Korean Central News Agency. She accused Lee or trying to create an “amicable image” while hosting a large-scale military exercise with the United States.

SEOUL, South Korea (AP) — North Korean leader Kim Jong Un condemned South Korean-U.S. military drills and vowed a rapid expansion of his nuclear forces to counter rivals, state media said Tuesday, as he inspected his most advanced warship being fitted with nuclear-capable systems.