The latest missile launch was carried out ahead of a key meeting between the US and Chinese presidents
North Korea has carried out its latest missile launch ahead of a US-China meeting where Kim Jong-Un's aggression is expected to be high on the agenda.
South Korea said a ballistic missile was fired from the eastern coastal town of Sinpo at 6.42am local time and flew for about 37 miles (60km) before landing in the Sea of Japan.
The launch came as South Korean and US troops were conducting annual military drills, which the North views as an invasion rehearsal.
The US military's Pacific Command said initial assessments suggest the KN-15 medium-range ballistic missile was fired from a land-based facility rather than a submarine.
South Korea's defence ministry said: "The military is keeping a close watch over North Korea's provocative moves and maintaining a high defence posture."
The missile was fired the day before Donald Trump hosts China's President Xi Jinping at his Mar-a-Lago resort in Florida.
Earlier this week the US President warned: "If China is not going to solve North Korea, we will. That is all I am telling you."
Following the latest launch, US Secretary of State Rex Tillerson said: "North Korea launched yet another intermediate range ballistic missile. The United States has spoken enough about North Korea. We have no further comment."
Pyongyang has continued work to develop a long-range missile capable of hitting the US mainland with a nuclear warhead and has so far staged five nuclear tests.
Mr Trump's tough talk followed a series of North Korean launches that Pyongyang described as practice for an attack on US bases in Japan.
The North successfully fired four ballistic missiles simultaneously in Japan's direction in February - six months after test-firing a submarine-launched missile 500km towards its near-neighbour.
Experts say Pyongyang - defying a UN ban on carrying out ballistic missile or nuclear tests - is still years away from developing a nuclear-capable SLBM (submarine-launched ballistic missile).