SEOUL/TOKYO (Reuters) - North Korea successfully launched a rocket on Wednesday, boosting the credentials of its new leader and stepping up the threat the isolated and impoverished state poses to opponents.

A screen shows a rocket being launched from a launch pad at the West Sea Satellite Launch Site, at North Korea's satellite control centre in Cholsan county, North Pyongan province, in this photo released by Kyodo December 12, 2012. North Korea successfully launched a rocket on Wednesday, boosting the credentials of its new leader and stepping up the threat the isolated and impoverished state poses to opponents. REUTERS/Kyodo

The rocket, which North Korea says put a weather satellite into orbit, has been labeled by the United States, South Korea and Japan as a test of technology that could one day deliver a nuclear warhead capable of hitting targets as far away as the continental United States.

“The satellite has entered the planned orbit,” a North Korean television news reader clad in traditional Korean garb announced, after which the station played patriotic songs with the lyrics “Chosun (Korea) does what it says”.

The rocket was launched just before 10 a.m. (0100 GMT), according to defense officials in South Korea and Japan, and was more successful than a rocket launched in April that flew for less than two minutes.

The North American Aerospace Defense Command (NORAD), a joint U.S.-Canadian military organization, said that the missile had “deployed an object that appeared to achieve orbit”.

North Korea followed what it said was a similar successful launch in 2009 with a nuclear test that prompted the U.N. Security Council to stiffen sanctions that it originally imposed in 2006 after the North’s first nuclear test.

North Korea is banned from developing nuclear and missile-related technology under U.N. resolutions, although Kim Jong-un, the youthful head of state who took power a year ago, is believed to have continued the state’s “military first” programs put in place by his late father, Kim Jong-il.

North Korea hailed the launch as celebrating the prowess of all three members of the Kim family to rule since it was founded in 1948.

“At a time when great yearnings and reverence for Kim Jong-il pervade the whole country, its scientists and technicians brilliantly carried out his behests to launch a scientific and technological satellite in 2012, the year marking the 100th birth anniversary of President Kim Il Sung,” its KCNA news agency said. Kim Il Sung, the current leader’s grandfather, was North Korea’s first leader.

The United States condemned the launch as “provocative” and a breach of U.N. rules, while Japan’s U.N. envoy called for a Security Council meeting. However, diplomats say further tough sanctions are unlikely from the Security Council as China, the North’s only major ally, will oppose them.

“The international community must work in a concerted fashion to send North Korea a clear message that its violations of United Nations Security Council resolutions have consequences,” the White House said in a statement.

U.S. intelligence has linked North Korea with missile shipments to Iran. Newspapers in Japan and South Korea have reported that Iranian observers were in the North for the launch, something Iran has denied.

Japan’s likely next prime minister, Shinzo Abe, who is leading in opinion polls ahead of an election on Sunday and who is known as a hawk on North Korea, called on the United Nations to adopt a resolution “strongly criticizing” Pyongyang.

A North Korean Foreign Ministry spokesman reiterated that the rocket was a “peaceful project”.

“The attempt to see our satellite launch as a long-range missile launch for military purposes comes from hostile perception that tries to designate us a cause for security tension,” KCNA cited the spokesman as saying.

“STUMBLING BLOCK”

China had expressed “deep concern” prior to the launch which was announced a day after a top politburo member, representing new Chinese leader Xi Jinping, met Kim Jong-un in Pyongyang.

On Wednesday, its tone was measured, regretting the launch but calling for restraint on any counter-measures, in line with a policy of effectively vetoing tougher sanctions.

“China believes the Security Council’s response should be cautious and moderate, protect the overall peaceful and stable situation on the Korean peninsula, and avoid an escalation,” Chinese Foreign Ministry spokesman Hong Lei told journalists.

Bruce Klingner, a Korea expert at the Heritage Foundation, said: “China has been the stumbling block to firmer U.N. action and we’ll have to see if the new leadership is any different than its predecessors.”

A senior adviser to South Korea’s president said last week it was unlikely there would be action from the United Nations and Seoul would expect its allies to tighten sanctions unilaterally.

Kim Jong-un, believed to be 29 years old, took power when his father died on December 17 last year and experts believe the launch was intended to commemorate the first anniversary of his death. The April launch was timed for the centennial of the birth of Kim Il Sung.

Wednesday’s success puts the North ahead of the South which has not managed to get a rocket off the ground.

“This is a considerable boost in establishing the rule of Kim Jong-un,” said Cho Min, an expert at the Korea Institute of National Unification.

There have been few indications the secretive and impoverished state, where the United Nations estimates a third of people are malnourished, has made any advances in opening up economically over the past year.

North Korea remains reliant on minerals exports to China and remittances from tens of thousands of its workers overseas.

Many of its 22 million people need handouts from defectors, who have escaped to South Korea, for basic medicines.

Given the puny size of its economy - per capita income is less than $2,000 a year - one of the few ways the North can attract world attention is by emphasizing its military threat.

It wants the United States to resume aid and to recognize it diplomatically, although the April launch scuppered a planned food deal.

The North is believed to be some years away from developing a functioning nuclear warhead although it may have enough plutonium for about half a dozen nuclear bombs, according to nuclear experts.

It has also been enriching uranium, which would give it a second path to nuclear weapons as it sits on big natural uranium reserves.

“A successful launch puts North Korea closer to the capability to deploy a weaponized missile,” said Denny Roy, a senior fellow at the East-West Center in Hawaii.

“But this would still require fitting a weapon to the missile and ensuring a reasonable degree of accuracy. The North Koreans probably do not yet have a nuclear weapon small enough for a missile to carry.”

The North says its work is part of a civil nuclear program although it has also boasted of it being a “nuclear weapons power”.

(This story has been refiled to clarify reference to NORAD in paragraph five)