Pyongyang regularly criticizes such drills as rehearsals for invasion and sometimes responds with weapons tests, but Seoul and Washington say they are purely defensive.

North Korean leader Kim Jong Un said his country needed to rapidly expand its nuclear armament and called U.S.-South Korea military exercises an "obvious expression of their will to provoke war," state media KCNA reported on Tuesday.

A move to lower tensions with Kim Jong Un's hermit kingdom has led to vital radio broadcasts of Christian material being cut off from the people who need it most.

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.

South Korean President Lee Jae Myung, who has been seeking to improve strained relations with Pyongyang, ordered on Monday his cabinet to prepare a partial step-by-step implementation of existing agreements with North Korea.

A California man has been sentenced to eight years in prison after admitting to shipping weapons and ammunition to North Korea

Kim said the "security environment" around North Korea is "getting more serious day by day" and "requires us to make a radical and swift change in the existing military theory and practice and rapid expansion of nuclearization," the official Rodong Sinmun newspaper reported, paraphrasing his remarks.

South Korea's new liberal president, Lee Jae Myung, said Friday that he will seek to restore a 2018 military agreement with North Korea aimed at reducing border tensions and urged Pyongyang to respond to Seoul's efforts to rebuild trust and revive dialogue.