UN Secretary General Antonio Guterres on Monday condemned North Korea's latest ballistic missile test and called for a united international response to the "further troubling violation" of UN resolutions.
His statement came ahead of an urgent UN Security Council meeting called to discuss Sunday's missile test -- nuclear-armed North Korea's first since US President Donald Trump assumed office.
The North's leader Kim Jong-Un "expressed great satisfaction over the possession of another powerful nuclear attack means which adds to the tremendous might of the country", state news agency KCNA said on Monday.
Guterres appealed "to the international community to continue to address this situation in a united manner," in an apparent reference to the United States and China, Pyongyang's ally.
"The DPRK leadership must return to full compliance with its international obligations and to the path of denuclearization," Guterres said in a statement, referring to North Korea.
Permanent UN Security Council members China and Russia joined a chorus of international criticism of the launch near the western city of Kusong.
The council will meet around 2200 GMT on Monday following a request by the United States, Japan and South Korea.
"I would certainly hope that the Security Council would come up with a clear and strong message," Japan's Ambassador Koro Bessho told reporters ahead of the meeting.
North Korea is barred under UN resolutions from carrying out ballistic missile launches or nuclear weapons tests.
But last year it conducted two nuclear tests and numerous missile launches in its quest to develop a nuclear weapons system capable of hitting the US mainland.
The latest missile -- said by Pyongyang to be able to carry a nuclear warhead -- flew east for about 500 kilometers (310 miles) before falling into the Sea of Japan (East Sea), South Korea's defense ministry said.
Footage on the North's state television showed the missile being moved on a newly developed mobile erector launcher.
It was launched at a near-vertical angle, igniting in mid-air after lift-off and switching direction while in flight.
Photos released by KCNA showed the missile blasting into the sky with a smiling Kim watching from the command center, and standing on the launch field surrounded by dozens of cheering soldiers and scientists.
It said Kim "personally guided" preparations for Sunday's test of what it described as a surface-to-surface "medium long range" Pukguksong-2, a "Korean-style new type strategic weapon system."
- Solid fuel -
KCNA said the missile was powered by a solid-fuel engine -- which needs a far shorter refuelling time than conventional liquid fuel-powered missiles, according to Yun Duk-Min of the Institute for Foreign Affairs and Security in Seoul.
"They leave little warning time and therefore pose a greater threat to opponents," he said, adding that such missiles are harder to detect by satellite before launch.
The North has previously made claims for its weapons capabilities that analysts consider unconvincing. But Seoul's military confirmed the North's claim on the solid-fuel engine.
Pyongyang's latest announcement was the first time a Pukguksong-2 has been mentioned, although last August it test-fired what it said was a submarine-launched ballistic missile (SLBM) marked as a Pukguksong-1, a name which translates as "North Star".
Kim said at the time that the missile put the US mainland and the Pacific within striking range.
An official with South Korea's Joint Chiefs of Staff told reporters the Pukguksong-2 appeared to have been fired based on the same "cold launch" technology used in last year's SLBM test.
The method -- in which a missile is initially propelled by compressed gas before its engine ignites mid-air -- is considered safer. It is also easier to hide the launch location.
North Korea claims it has developed an intercontinental ballistic missile (ICBM) capable of hitting the US mainland but has not tested one as yet.
- Armed provocation -
The South has said that Sunday's launch was intended as a test for Trump, who responded by pledging "100 percent" support for Washington's key regional ally Japan.
Trump has pressed China, the north's sole major ally and key trade partner, to play a bigger role in restraining its wayward neighbor.
In Tokyo Japan's top government spokesman Yoshihide Suga said Monday China plays an "extremely important" role and called on Beijing to take "constructive action".
China's foreign ministry spokesman Geng Shuang said it opposes North Korean missile launches that violate UN resolutions.
Russia's foreign ministry called the launch "a demonstration of contempt for UN Security Council resolutions".
But Joel Wit, a senior fellow at the US-Korea Institute at Johns Hopkins University, said more provocations were likely in response to upcoming US-South Korean military exercises.