The UN Security Council is to hold an emergency meeting later following North Korea’s launch of a long-range rocket.
The meeting was requested by South Korea, Japan and the US to agree on a collective response to the launch.
Pyongyang said it fired the rocket to place a satellite in orbit, but critics believe the real purpose was to test a ballistic missile.
Sunday’s launch comes weeks after North Korea held a fourth nuclear test – both acts violate UN resolutions.
The launch of the rocket was hailed by North Korean media as a “fascinating vapour… trailing in the clear and blue sky in spring of February on the threshold of the Day of the Shining Star”.
A statement said a new Earth observation satellite, Kwangmyongsong-4, had successfully been put into orbit less than 10 minutes after lift-off from the Sohae space centre in North Phyongan province.
Hailing it as part of the country’s peaceful space programme, a state TV newsreader said the launch had been ordered by North Korea’s leader Kim Jon-un and more satellite launches were planned for the future.
South Korean MPs were told in a closed-door briefing by the country’s spy agency later on Sunday that the launch should be treated as a ballistic missile test as the satellite it put into orbit would be useless.
The payload was presumed to weigh 200kg (440lbs), double the size of the one launched in 2012, but much lighter than the 800-1,500kg usual for a satellite.
They were also reportedly told that North Korea has the technology for intercontinental ballistic missiles and is preparing a fifth nuclear test, South Korean news agency Yonhap reported.