Musudan missile could be capable of striking targets across South Korea and Japan
North Korea is believed to have unsuccessfully attempted to fire a powerful mid-range missile.
South Korea and the United States said the launch ended in failure after the projectile reportedly exploded soon after lift-off.
The South Korean Joint Chiefs of Staff said the attempt was made near an airport in the North's North Pyongan province.
US Strategic Command said it detected the activity just after midday on Saturday Korea time.
The missile is believed to have been a ballistic Musudan which North Korea has now test-fired seven times, with one partial success.
The rocket, which has a range of anywhere between 1,550 and 2,500 miles, could be capable of striking targets across South Korea and Japan, as well as US military bases as far away as Guam.
UN resolutions prohibit North Korea from using ballistic missile technology, and this latest test came as the UN Security Council is debating fresh sanctions on Pyongyang following its fifth nuclear test in September.
The action has brought harsh criticism from the US.
"We strongly condemn this and North Korea's other recent missile tests, which violate UN Security Council Resolutions explicitly prohibiting North Korea's launches using ballistic missile technology," said Commander Gary Ross, a Pentagon spokesman.
"Our commitment to the defence of our allies, including the Republic of Korea and Japan, in the face of these threats, is ironclad. We remain prepared to defend ourselves and our allies from any attack or provocation."
He said the US would raise concerns at the UN.