North Korea said Tuesday that leader Kim Jong Un was briefed on his military's plans to launch missiles into waters near Guam as part of an effort to create "enveloping fire" near the U.S. military hub in the Pacific.

Defence Secretary Jim Mattis says the U.S. will "take out" any North Korean missile it detects is heading for American soil, including the Pacific island of Guam.

North Korea has threatened to lob four intermediate-range missiles into the waters near the U.S. territory of Guam.