China has reiterated that any UN response to North Korea's rocket launch should be "prudent and moderate," after the U.S. urged Beijing to pressure Pyongyang to adhere to its international obligations.
Foreign Ministry spokesman Hong Lei said Thursday the response should be conducive to maintaining peace and stability on the Korean peninsula, and it should avoid escalating tensions.
China is North Korea's top ally and largest trading partner, and supplies the impoverished country with crucial humanitarian aid.
On Wednesday, the U.S. urged China to exert its influence on Pyongyang, during a meeting between U.S. senior defense official James Miller and Chinese General Qi Jianguo. The White House has called the launch a "highly provocative act" that threatens regional security.
Wednesday's launch prompted a wave of international criticism from countries including China. The UN Security Council said the launch violated resolutions banning Pyongyang from carrying out missile or nuclear tests.
North Korea says it fired the long-range rocket with the intention of putting a weather satellite into orbit.
On Thursday, South Korea said the satellite carried by the rocket is orbiting the Earth normally, but noted it is working to learn if the satellite is functioning properly.
Defense Ministry spokesman Kim Min-seok said Seoul does not know what kind of mission the satellite is conducting. But he denounced the launch as a disguised ballistic missile test.
Kim also said the launch shows North Korea is closer to developing the technology needed to fire an intercontinental ballistic missile.
"A nuclear warhead weighs about 650 kg. [To have the full capability to launch an intercontinental ballistic missile [ICBM], North Korea needs to concentrate on putting more effort into increasing weight on board. Like I mentioned yesterday, another type of technology is needed when the missile re-enters the earth's atmosphere. I think North Korea will try to develop those technologies. We have analyzed that the North already has a large portion of the technology required to complete this successfully," he said.
The U.S. military has confirmed "an object" appeared to reach orbit, but says it is working to determine the nature of the device and whether it is successfully communicating with North Korea.
The UN Security Council has imposed two rounds of sanctions against North Korea, following nuclear tests in 2006 and 2009. After a failed North Korean rocket launch in April, the council ordered foreign assets seized from several North Korean companies linked to financing and procuring weapons and missile technology.