North Korea says its new leader, Kim Jong Un, has ordered troops to launch a powerful retaliatory strike against South Korea if provoked.
The official Korean Central News Agency reported Sunday that Kim issued the order during a visit to front-line military units, including one that shelled South Korea's Yeonpyeong Island in 2010, killing four people.
South Korean and U.S. troops are to kick off annual computer-simulated war games Monday. North Korea has threatened a "sacred war" over the drills.
A senior U.S. envoy said Saturday that ties between the two Koreas need to improve before North Korea and the United States can achieve real progress in their relationship.
Glyn Davies made the comments in Seoul after nuclear talks in Beijing with North Korean officials.