State news agency KCNA described the device, fired into the Sea of Japan, as a “surface-to-surface medium-to-long-range ballistic missile”.
South Korea's defence ministry called it an armed provocation to test the response of US President Donald Trump.
North Korea's latest ballistic missile test has been widely condemned.
It said the missile used a solid-fuel engine, which gives ballistic missiles greater range and means they can be readied for launch faster than liquid-fuel missiles.
It was a new version of a missile test-fired from a submarine in August 2016 and was fired in a high arc in consideration of neighbouring countries, the report said.
Kim Jong-un “expressed great satisfaction” over the test launch, which added “to the tremendous might of the country”, the state news agency said.
Credit to BBC