North Korea has test-fired a ballistic missile from a region north of its capital but it appears to have failed, South Korea's military says.
The act defies intense pressure from the US and the reclusive state's main ally, China.
Yonhap news agency said the missile appeared to have blown up a few seconds into flight.
US President Donald Trump took to Twitter to condemn the move.
"North Korea disrespected the wishes of China & its highly respected President when it launched, though unsuccessfully, a missile today. Bad!"
The US military has tracked a North Korean ballistic missile launch but officials say the missile did not leave North Korean territory and did not pose a threat to North America.
Commander Dave Benham, a spokesman for US Pacific Command, said the missile launch took place at 10:33am on Friday, Hawaii time (8.33am Saturday, NZ time), from near the Pukchang airfield.
The test came as US Secretary of State Rex Tillerson warned the United Nations that failure to curb North Korea's nuclear and ballistic missile programs could lead to "catastrophic consequences".
Mr Trump told Reuters in an interview on Thursday a "major, major conflict" with North Korea was possible over its nuclear and ballistic missile programs.
Mr Trump praised Chinese leader Xi Jinping for "trying very hard" to rein in Pyongyang.
But both China and Russia rebuked Washington's threat of military force at a meeting of the UN Security Council on the matter.
Tensions on the Korean peninsula have been rising as North Korea celebrates a number of key anniversaries, with both sides staging major military drills.
In a show of force, the United States is sending the USS Carl Vinson aircraft carrier group to waters off the Korean peninsula, where it will join the USS Michigan, a nuclear submarine that docked in South Korea on Tuesday. South Korea's navy has said it will hold drills with the US strike group.
Timeline of past North Korean missile tests
- August 1998: North Korea fires a multistage, long-range missile called Taepodong-I over Japan into the Pacific Ocean. North Korea called it a satellite launch.
- July 2006: North Korea test-fires a Taepodong-2 missile, which the US said failed after launch.
- October 2006: North Korea conducts first nuclear test.
- April 2009: North Korea says it successfully launches three-stage Unha-2 rocket carrying satellite. Washington says it failed.
- May 2009: North Korea explodes a nuclear device underground.
- April 2012: A slightly modified Unha-3 rocket explodes just after take-off. The North concedes failure.
- December 2012: North Korea again launches a Unha-3 rocket, saying it successfully put a satellite into orbit. US officials confirm an object in orbit, but no signal is detected.
- February 2013: North Korea carries out third nuclear test.
- January 6, 2016: North Korea says it successfully tests a hydrogen bomb.
- April 15, 2016: North Korea attempts to launch a Musudan missile but fails.
- February 7, 2016: North Korea launches a long-range rocket, which it says put a satellite into orbit
- June 22, 2016: North Korea conducts two tests of an intermediate range Musudan missile after four failed launches of the same kind.
- July 18, 2016: North Korea fires three ballistic missiles off its east coast with a 500 km-600 km range.
- August 3, 2016: North Korea fires two missiles, one of them landing in Japan's economic exclusion zone.
- August 24, 2016: North Korea launches ballistic missile from a submarine, which flies 500 km.
- September 5, 2016: North Korea fires three ballistic missiles about 1000 kms, one of which enters Japan's air defence zone
- September 9, 2016: North Korea conducts fifth nuclear test
- September 20, 2016: North Korea says it complete ground test of a new rocket engine, which South Korea says is likely to be used for a long-range missile.
- February 12, 2017: North Korea fires intermediate-range Pukguksong-2 ballistic missile into nearby seas.
- March 6, 2017: North Korea fires four ballistic missiles, three of them falling into Japan's exclusive economic zone.
- March 19, 2017: North Korea announces rocket engine test, saying it will help country achieve "world-class satellite launch capability".
- March 22, 2017: A North Korean missile appears to explode just after launch.
- April 5, 2017: North Korea fires ballistic missile into the sea off its east coast. US officials say it appears to be a liquid-fuelled, extended-range Scud missile.