The US on Sunday denied North Korea's claims that it had successfully launched a satellite into space. It came after the communist nation fired a rocket over Japan, defying Washington, Tokyo and others who suspect the launch was cover for a test of its long-range missile technology. US President Barack Obama said the move threatens the security of nations "near and far." Liftoff took place at 11:30 a.m. (0230 GMT) from the coastal Musudan-ri launch pad in northeastern North Korea, the South Korean and US governments said. The multistage rocket hurtled toward the Pacific, reaching Japanese airspace within seven minutes, but no debris appeared to hit its territory, officials in Tokyo said. Four hours after the launch, North Korea said an experimental communications satellite reached outer space in just over nine minutes and is orbiting Earth, the state-run Korean Central News Agency said from Pyongyang. "The satellite is transmitting the melodies of the immortal revolutionary paeans 'Song of Gen. Kim Il Sung' and 'Song of Gen. Kim Jong Il' as well as measurement data back to Earth," it said, referring to the country's late founder and his son, its current leader. But the US military said "no object entered orbit." North American Aerospace Defense Command and US Northern Command officials said in a statement that the first stage of the rocket fell into the waters between Korea and Japan, while the two other stages, and its payload, landed in the Pacific Ocean. The launch was a bold act of defiance against Obama, Japanese leader Taro Aso, Hu Jintao of China and others who pressed North Korea in the days leading up to liftoff to cancel a move they said would threaten peace and stability in Northeast Asia. The UN Security Council approved an emergency session for Sunday afternoon in New York. "North Korea has ignored its international obligations, rejected unequivocal calls for restraint and further isolated itself from the community of nations," Obama said in Prague, urging the North to refrain from further "provocative" actions. He said the move was a clear violation of UN Security Council Resolution 1718, which prohibits North Korea from conducting ballistic missile-related activities of any kind, and demands an international response. "North Korea broke the rules once more by testing a rocket that could be used for a long range missile," Obama said. "This provocation underscores the need for action - not just this afternoon at the UN Security Council, but in our determination to prevent the spread of these weapons." In Tokyo, Aso said the launch was "an extremely provocative act that cannot be overlooked." China, North Korea's biggest source of economic aid and diplomatic support, urged all sides to maintain calm and exercise restraint. It offered to play a "constructive role," though some say it could use its veto power to block a unified response to the launch at the Security Council. Russia, which shares a border with North Korea, also called for calm. "We urge all states concerned to show restraint in judgments and action in the current situation, and to be guided by objective data on the nature of North Korea's launch," a Foreign Ministry statement said. North Korea says the launch of the "Kwangmyongsong-2" satellite was a peaceful bid to develop its space program. But the US, South Korea, Japan and others suspect the launch was a guise for testing the regime's long-range missile technology - a step toward eventually mounting a nuclear weapon on a missile capable of reaching Alaska and beyond. They contend it violates Resolution 1718, part of efforts to force North Korea to shelve its nuclear program and halt long-range missile tests. The European Union also "strongly" condemned the launch. Japan's UN mission immediately requested a meeting of the 15-nation council, spokesman Yutaka Arima said. Mexico, which holds the 15-nation council's presidency this month, set the meeting for 3 p.m. EDT (1900 GMT), spokesman Marco Morales said. UN Secretary-General Ban Ki-moon said he regretted North Korea's move "against strong international appeal" at a time when nuclear disarmament talks involving six nations remain stalled. "Given the volatility in the region, as well as a stalemate in interaction among the concerned parties, such a launch is not conducive to efforts to promote dialogue, regional peace and stability," Ban said in a statement from Paris. At the United Nations, diplomats have begun discussing ways to affirm existing sanctions on North Korea. Envoys said permanent council members US, Britain and France are unlikely to secure agreement on new sanctions from veto holders Russia and China. They spoke on condition of anonymity because of the sensitive nature of the discussions. North Korea, which says its participation in a UN space treaty protects its right to send a satellite into orbit, took pains to alert international maritime and aviation authorities of the rocket's flight path, in marked contrast to 2006, when it carried out a surprise launch. "Even if a satellite was launched, we see this as a ballistic missile test," Japan's chief Cabinet spokesman Takeo Kawamura said. Japan had threatened to shoot down any debris from the rocket if the launch went wrong, and positioned batteries of interceptor missiles on its coast and radar-equipped ships in its northern seas to monitor the liftoff. Russia also scrambled fighter jets to monitor the launch, while US and South Korea sent warships to nearby waters, reports said. No attempt at interception was made because no debris fell onto its territory, Japan's Defense Ministry said. However, Japan threatened to add more bilateral sanctions onto those it imposed after the July 2006 launch of a similar Taepodong-2 long-range missile that fizzled 42 seconds after takeoff. South Korea, which technically remains at war with the North because their three-year conflict ended in 1953 in a truce rather than a peace treaty, put its forces on heightened alert. North Korea, one of the world's poorest nations, is led with absolute authority by leader Kim Jong Il, who is poised to preside over the first session of the country's new parliament on Thursday. The appearance will be his first major public appearance since reportedly suffering a stroke last August. Amid the controversy over the rocket launch, North Korea announced last week it would put two American reporters detained at the border with China on trial for allegedly entering the country illegally and engaging in "hostile acts." Laura Ling and Euna Lee, reporters for former US Vice President Al Gore's Current TV media venture, were seized by North Korean soldiers on March 17.