South Korea's military said it had detected the launch of a long-range ballistic missile fired from the Pyongyang area around 10 am (0100 GMT), France 24 reported.
"The ballistic missile was fired on a lofted trajectory and flew 1,000 km (620 miles) before splashing down in the East Sea," the Joint Chiefs of Staff said, referring to the body of water also known as the Sea of Japan.
Pyongyang last fired one of its most powerful intercontinental ballistic missiles in April -- the purportedly solid-fuelled Hwasong-18 -- and in February launched a Hwasong-15, which flew a similar 989 km.
The flight time of around 70 minutes is also similar to some of North Korea's previous ICBM launches, experts said.
Wednesday's launch came after North Korea on Monday accused a US spy plane of violating its airspace and condemned Washington's plans to deploy a nuclear missile submarine near the Korean peninsula.
A spokesperson for the North Korean Ministry of National Defence said the United States had "intensified espionage activities beyond the wartime level", citing "provocative" spy plane flights over eight straight days this month.
AMK/PR