North Korean rocket launch succeeds

North Korea appears to have successfully sent a satellite into orbit, US military officials have said after the regime launched a long-range rocket in defiance of international pressure to abandon what many see as a test of its ballistic missile capability.

The US, Japan and other countries immediately condemned the launch as a violation of international sanctions amid calls for further measures against Pyongyang.

US missile warning systems detected the rocket after it lifted off from a site on North Korea's west coast, said officials at the North American Aerospace Defence Command (Norad), adding that the rocket deployed an object that appeared to achieve orbit around Earth.

Norad said the three-stage Unha rocket had taken its expected southerly course, with its first stage falling into the Yellow Sea west of South Korea and the second landing in the sea east of the Philippines.

"Initial indications are that the missile deployed an object that appeared to achieve orbit," Norad said. "At no time was the missile or the resultant debris a threat to North America." South Korea and Japan said they were unable to immediately confirm Norad's report.

In a triumphalist TV announcement accompanied by stirring string music and images of a snow-covered landscape, North Korea's state media said the country had successfully launched a rocket carrying a satellite.

The launch from the Tongchang-ri site in North Pyongan province at 9.49am local time took the world by surprise. Speculation had mounted that it would be delayed by at least several days while North Korean engineers fixed what had been described as a "technical deficiency" in the rocket's first-stage control engine module.

North Korea had said it was extending the original 13-day launch window by a week until 29 December. On Tuesday satellite images suggested that the rocket had been emptied of fuel and removed from its launchpad.

Wednesday's apparent success has raised the stakes in international efforts to pressure Pyongyang into abandoning its ballistic and nuclear missile programmes.

It follows four previous unsuccessful attempts to put satellites into space using long-range rockets. The most recent attempt came on 13 April – two days before the centennial of the birth of the country's founder and Kim Jong-un's grandfather, Kim Il-sung – when another three-stage rocket disintegrated less than two minutes after lift-off. In an unusual show of candour the regime quickly admitted that the launch had been a failure.

But if reports about the success of this latest launch are correct, the regime can reasonably claim to have significantly improved its technological know-how.

The North has frequently dismissed accusations that it uses rocket launches as a cover to test its ballistic missile technology which, if perfected, could give the regime a projectile capable of reaching the US mainland. North Korea insists the rocket launch was intended to send an Earth observation satellite into orbit.

North Korea is believed to have weaponised enough plutonium for about half a dozen rudimentary nuclear weapons, although experts say it has yet to develop a warhead small enough to mount on a missile.

Daniel Pinkston, deputy project director of the North East Asia programme at the International Crisis Group, said the earlier-than-expected launch suggested there had either been a misperception along the way or a deliberate operation to mislead observers.

But Pinkston said no one should be surprised by the North's decision to fire another rocket. "It would be absolutely illogical for them not to do it," he said.

"They have invested tremendous amounts of resources in this over decades. They want to possess the capabilities: this is dual use technology with both military and peaceful applications. They are supposed to be a strong and prosperous and powerful country ... this is what you do."

The apparently successful launch will have bolstered the credentials of the North's 29-year-old leader, Kim Jong-un, who was anointed just under a year ago after the death on 17 December 2011 of his father, Kim Jong-il. Reports from North Korea had said the latest rocket launch would proceed "at the behest" of the late dictator.

"If the rocket actually makes it into space and releases a working satellite it will be a major moment in the country's history and a huge propaganda success for the North Korean regime," said Martyn Williams of the North Korea Tech blog.

The South Korean military detected the rocket as soon as it was airborne, according to the South's Yonhap news agency. "Shortly after liftoff an Aegis radar system in the Yellow Sea detected the move," a military official was quoted as saying.

The US, Japan and South Korea had applied pressure on the North Korean regime to abandon the launch, saying it violated UN security council resolutions banning it from using ballistic missile technology and would invite further sanctions. The UN security council imposed tough sanctions after the North conducted nuclear weapons tests in 2006 and 2009.

China, the regime's only major diplomatic ally and chief benefactor, voiced "deep concern" but is expected to oppose further sanctions. Japan on Wednesday requested an emergency meeting of the UN body to discuss its response.

Britain's foreign secretary, William Hague, said: "I strongly condemn the satellite launch today." The UK government would summon the North Korean ambassador in London, he said. "This provocative act will increase tensions in the region. I deplore the fact that [North Korea] has chosen to prioritise this launch over improving the livelihoods of its people.

"It is essential that [North Korea] refrain from further provocative action and take constructive steps towards denuclearisation and lasting peace and stability on the Korean peninsula."

The anticipated launch had raised anxiety levels in the region, days before both Japan and South Korea elect new leaders and weeks after China completed its once-in-a-decade leadership change.

Japan had positioned missile defence systems on the southern island of Okinawa but reported that no debris had fallen on to its territory.

South Korea's president, Lee Myung-bak, convened an emergency security meeting. The country had positioned three Aegis warships equipped with SPY-1 radar off its western and southern coasts to track the rocket's path.

Ban Ki-moon deplored the launch, said the office of the UN secretary general.