SEOUL: South Korea and the U.S. military conducted rare missile drills and an American supercarrier repositioned east of North Korea after Pyongyang flew a missile over Japan, one of the allies' sharpest responses since 2017 to a North Korean weapon test.

Nuclear-armed North Korea test-fired an intermediate-range ballistic missile (IRBM) farther than ever before on Tuesday, sending it soaring over Japan for the first time in five years and prompting a warning for residents there to take cover.

The White House National Security Council called North Korea's latest test "dangerous and reckless" and the U.S. military and its allies have stepped up displays of force. 

South Korean and American troops fired a volley of missiles into the sea in response, South Korea's Joint Chiefs of Staff said on Wednesday, and the allies earlier staged a bombing drill with fighter jets in the Yellow Sea. 

The USS Ronald Reagan, an American aircraft carrier that made its first stop in South Korea last month for the first time in years, will also return to the sea between Korea and Japan with its strike group of other warships. The South Korean military called it a "highly unusual" move designed to show the allies' resolve to respond to any threats from North Korea.

U.S. Indo-Pacfic Command did not immediately respond to a request for comment.

The South Korean military separately confirmed that one of its Hyunmoo-2C missiles failed shortly after launch and crashed during the drill, but that no one was hurt.

Footage shared on social media by a nearby resident and verified by Reuters showed smoke and flames rising from the military base.

The fire was caused by burning rocket propellant, and although the missile carried a warhead, it did not explode, South Korea's military said. 

It apologised for causing residents to worry.

It's not rare for military hardware to fail, and North Korea has suffered several failed missile launches this year as well.

The Hyunmoo-2C is one of the South's latest missiles, however, and analysts say its capability as a precision "bunker buster" make it a key part of Seoul's plans for striking the North in the event of a conflict.

The fiery failure threatened to overshadow Seoul's efforts to demonstrate military prowess in the face of North Korea's increasing capabilities.

In its initial announcement of the drill, the South Korean military made no mention of the Hyunmoo-2C launch or its failure, but later media briefings were dominated by questions about the incident.

President Yoon Suk-yeol, who has made such displays of military force a cornerstone of his strategy for countering the North, had vowed that the overflight of Japan would bring a decisive response from his country, its allies and the international community.

SECURITY COUNCIL MEETING

The U.N. Security Council will meet on Wednesday to discuss North Korea at the request of the United States, despite China and Russia telling council counterparts they were opposed to an open meeting of 15-member body. They argued that the council's reaction should be conducive to easing the situation on the Korean Peninsula, diplomats said. 

U.S. President Joe Biden and Japanese Prime Minister Fumio Kishida condemned North Korea's test in the "strongest terms," the European Union called it a "reckless and deliberately provocative action", and U.N. Secretary-General Antonio Guterres condemned the launch and said it was a violation of Security Council resolutions.

It was the first North Korean missile to follow a trajectory over Japan since 2017, and its estimated 4,600 km (2,850 mile) flight was the longest for a North Korean test, which are usually "lofted" into space to avoid flying over neighbouring countries.

Analysts and security officials said it may have been a variant of the Hwasong-12 IRBM, which North Korea unveiled in 2017 as part of what it said was a plan to strike U.S. military bases in Guam.

Neither North Korea's government nor its state media have reported on the launch or disclosed what type of missile was used.

The flight has increased concerns that North Korea may soon conduct an expected nuclear test, which would be the first since 2017.

South Korean officials said North Korea had completed preparations for a test and might use a smaller weapon meant for operational use, or a big device with a higher yield than in previous tests.

The launch was a "reckless and deliberately provocative action" that violated U.N. security council resolutions, a European Union spokesperson said.