A White House official on Sunday confirmed that North Korea had test-fired a medium-range ballistic missile, despite threats of tougher US sanctions over its missile tests.
"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 Sunday from Pukchang in South Pyongan province but that it travelled about 500 kilometres (310 miles).
The latest launch came just a week after a similar test sparked international condemnation and a warning from Washington that new sanctions could be imposed on Pyongyang.