The long-planned Minuteman 3 test was called off over concerns it could aggravate tension even more, according to a a senior defense official.
In addition to the missile test, the U.S. has postponed congressional testimony by Gen. James Thurman, the top U.S. military commander in South Korea.
Thurman will stay in Seoul out of caution rather than travel to Washington to appear this coming week before congressional committees. Thurman is expected to testify at a later date.
Top U.S. military officer Gen Martin Dempsey said the U.S. has been preparing for further provocations or action, "considering the risk that they may choose to do something" on one of two nationally important anniversaries in April - the birth of North Korean founder Kim Il Sung and the creation of the North Korean army.
The North's military said last week that it was authorized to attack the U.S. using "smaller, lighter and diversified" nuclear weapons. North Korea also conducted a nuclear test in February and in December launched a long-range rocket that could potentially hit the continental U.S.
Amid the mounting tension, the U.S. has moved two of the Navy's missile-defense ships closer to the Korean peninsula, and a land-based system is being deployed to the Pacific territory of Guam later this month. In March, the Pentagon announced longer-term plans to strengthen its U.S.-based missile defenses.
North Korea has told other nations that it will be unable to guarantee diplomats' safety in the North's capital beginning Wednesday. In reaction, South Korean President Park Geun-hye's national security director said the North may be planning a missile launch or another provocation around Wednesday, according to a presidential spokesperson.
In Washington, an adviser to President Barack Obama said "we wouldn't be surprised if they did a test. They've done that in the past."
The Associated Press contributed to this report.
