U.S. military forces "stand ready" to safeguard Guam after after North Korea threatened to fire ballistic missiles toward the American Pacific island territory, the White House said early Saturday.

During a call with Guam Governor Eddie Calvo, President Donald Trump "reassured" him that "United States forces stand ready to ensure the safety and security of the people of Guam, along with the rest of America," a statement read.

It said White House Chief of Staff John Kelly spoke with Calvo separately during an earlier call.