WASHINGTON (AFP) - North Korea appears to be readying for some kind of a rocket launch, a US defence official said on Thursday, though it did not appear to be a ballistic missile.
The official's comments came after Japanese media reported that satellite images showed Pyongyang seemed to be setting up a long-range ballistic missile launch from the Dongchang-ri site in North Korea's west.
"The indications are that they are preparing for some kind of launch," the US official told AFP, speaking on condition of anonymity.
The official did not say where in North Korea the preparations were taking place, but said people on the ground appeared to be readying for "a regular space launch."
"Could be for a satellite or a space vehicle - there are a lot of guesses. North Korea does this periodically, they move things back and forth... There's nothing to indicate it's ballistic-missile related," the official said.
Citing an anonymous government source, Kyodo News in Japan said the satellite imagery had been collected over the past several days.
Increased movements of people and vehicles were seen around the launch site, which has now apparently been covered over, Japanese national broadcaster NHK said, citing a source familiar with Japan-South Korea relations.
The United States regularly monitors North Korea from space, while Japan began its own satellite monitoring of the country in 2003.
North Korea is banned under UN Security Council resolutions from carrying out any launch using ballistic missile technology, although repeated small-range missile tests have gone unpunished.
The development parallels events in December 2012, when Pyongyang put a satellite into orbit with its Unha-3 carrier.
The international community condemned the 2012 launch as a disguised ballistic missile test, resulting in a tightening of UN sanctions, despite Pyongyang's claim that it was a scientific mission.
The latest activity comes amid a flurry of diplomatic activity over possible further sanctions against Pyongyang for conducting its fourth nuclear test earlier this month.
Pyongyang said the blast was a miniaturised hydrogen bomb - though experts have largely dismissed the claim.
Washington is pushing for a strong United Nations response, including enhanced sanctions.
But China, North Korea's chief diplomatic protector and economic benefactor, is reluctant, despite ties becoming strained in recent years as Beijing's patience wears thin with its neighbor's ambitions for nuclear weapons.
US Secretary of State John Kerry met with his Chinese counterpart Wang Yi in Beijing on Wednesday and said they had agreed to mount an "accelerated effort" to try to resolve their differences on a new resolution.
Kerry, who said nuclear-armed North Korea poses an "overt threat, a declared threat to the world," acknowledged that the two had not agreed on the "parameters of exactly what it would do or say."
South Korean defence ministry spokesman Kim Min-Seok declined to confirm or deny the Japanese media reports, but said the South's military was monitoring for any signs of a long-range missile launch.
"In the past, North Korea always fired a long-range missile ahead of a nuclear test. But since it didn't this time, we are concerned that it could launch one" afterwards, Kim said.
Kim also stressed that Pyongyang used to notify China and the US before carrying out nuclear tests, though this time did not.
"We believe that North Korea could launch grave provocations by surprise - without pre-warning - from now on."
The possible preparation of a launch also came after the North said it carried out a submarine-launched ballistic missile test in December.
Pyongyang hailed that test as a great success and released a video that researchers at the California-based James Martin Center for Nonproliferation Studies concluded had been heavily doctored and edited to cover up a "catastrophic" failure.
The North claims it has developed long-range missiles capable of hitting the United States, but many experts say Pyongyang is still years away from obtaining a credible intercontinental ballistic missile capability.