"We are aware that North Korea launched an MRBM. This system, last tested in February, has a shorter range than the missiles launched in North Korea's three most recent tests," the official said in Saudi Arabia, where US President Donald Trump is on a two-day visit.
Officials in Seoul had earlier reported the test, with South Korea's Joint Chiefs of Staff saying it could not yet identify the type of missile fired today from Pukchang in South Pyongan province but that it travelled about 500 kilometres (310 miles).