Rocket launch was a failure - analysts

North Korea has failed in its third attempt since 1998 to build an accurate long-range missile, analysts say, undercutting its image as a defiant state able to project its power across the ocean. The communist North claimed it had launched a satellite on Sunday that was now circling the globe, transmitting data and patriotic songs praising secretive leader Kim Jong-Il.

But the US and South Korea say the launch failed to get anything into orbit, and experts said the rocket's second and third stages apparently did not separate as planned.

"(It) was a failure," Joseph Bermudez of Jane's Information Group told AFP.

"It seems to indicate that North Korea has not been able to demonstrate a reliable system capable of being an ICBM or a space launch vehicle."

Washington, Seoul and Tokyo said the launch was a smoke-screen for testing a Taepodong-2 intercontinental ballistic missile, which at maximum range could theoretically hit the US states of Alaska and Hawaii.

Mr Bermudez said current information indicated the second stage did not drop, meaning the rocket was too heavy to sustain flight. He described it as a step back from the 1998 launch of a Taepodong-1, which achieved first- and second-stage separation while the third stage failed. The only previous test of a Taepodong-2, in 2006, lasted just 40 seconds. Daniel Pinkston, senior analyst with the International Crisis Group think-tank, also assessed the exercise as a failure based on reports available so far.

"There was some problem with the separation of the second and third stage," he said.

After the 2006 test North Korea tested an atomic bomb, which led the UN Security Council to pass a resolution barring the communist state from further missile-related activities.

During long-running six-nation nuclear disarmament talks, North Korea has repeatedly said it needs a deterrent against any attack by the US, which it accuses of wanting to bring down the regime.

While the North is not believed to have configured a warhead for the Taepodong-2, a successful launch on Sunday would have added to international concerns about the North's capabilities.

South Korea's National Intelligence Service described it as a successful rocket test but a failed satellite launch, according to lawmakers who attended a closed-door briefing of parliament's intelligence committee. Chae Yeon-Seok of the Korea Aerospace Research Institute called it "a big step forward in the North's rocket technology."

But the ICG's Pinkston said the stated aim of the exercise - putting a satellite into orbit - is technically easier than delivering a warhead, which must re-enter the atmosphere and detonate.

Nuclear expert Joseph Cirincione, president of the non-profit Ploughshares Fund, told CNN that he believed it would take years for Pyongyang to develop a serious missile threat to the US.

"This third failure to create such a missile in as many attempts since 1998 likely represents the upper limits of what the country can do by stretching and adapting the Scud technology it acquired from the former Soviet Union."

Some analysts suggested the latest failure might help convince the North that its hugely expensive weapons are not buying the country security, giving Barack Obama's US administration a chance to get Pyongyang to abandon them.

"This creates an opportunity to convince them there are other ways to ensure their security," Mr Pinkston said. David Wright, of the Union of Concerned Scientists, told the New York Times that the incident might "open a window of opportunity" with Pyongyang - which Mr Pinkston said would be engaged in "soul searching" after the failure.