WASHINGTON, Feb 5 (Reuters) - Satellite images taken this week of North Korea's Sohae rocket launch site show apparent fueling activity seen in the past one to two weeks before a rocket launch, a U.S. think tank said on Friday.
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North Korea has told U.N. agencies it will launch a rocket carrying what it called an earth observation satellite some time between Feb. 8 and Feb. 25, triggering international opposition from governments that see it as a long-range missile test.
Commercial satellite images from Wednesday and Thursday show the arrival of tanker trucks at the launch pad, said Washington-based 38 North, a North Korea-monitoring project. It said the presence of the trucks likely indicated the filling of tanks within bunkers at the site rather than a rocket itself.
"In the past, such activity has occurred one to two weeks prior to a launch event and would be consistent with North Korea's announced launch window," the report said.
A U.S. defense official said on Thursday activity detected at the site was consistent with a launch in the time frame given by Pyongyang. On Friday, a U.S. government source said U.S. intelligence agencies believed North Korea could be ready by the U.S. Super Bowl kickoff on Sunday, which will be Monday, Korea time.
On Friday, U.S. President Barack Obama spoke by telephone with President Xi Jinping of China, North Korea's main ally and neighbor and agreed that North Korea's planned launch would represent a "provocative and destabilizing action," the White House said.
Obama and Xi also said they would coordinate efforts to respond to North Korea's nuclear test last month and said they would not accept North Korea as a nuclear weapon state.
"The leaders emphasized the importance of a strong and united international response to North Korea's provocations, including through an impactful UN Security Council Resolution," the White House said.
Washington and Beijing have appeared divided over how to respond to North Korea, with the United States urging tougher sanctions and China stressing the need for dialog.
Earlier on Friday, Xi told South Korea's president that China was dedicated to maintaining peace and stability on the Korean peninsula.
"We hope all sides can act bearing in mind the broader picture of maintaining peace and stability on the peninsula, and calmly deal with the present situation," China's Foreign Ministry quoted Xi as saying.
The 38 North report said activity could also be seen around a building at the launch site used in the past to receive and assemble rocket stages.
It said the imagery showed vehicles including one or two buses and a crane and added: "This level of activity compares favorably to that seen prior to the previous launch in 2012."
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The report said the images indicated no significant changes at the launch pad itself, where work platforms on the gantry towers remained folded forward. It said coverings obscured whether a space-launch vehicle was present on the pad.
"Although there is no activity indicating an imminent launch, the gantry tower and launch pad complex appear to be capable of conducting a launch within the announced launch window," it said.
North Korea says it has a sovereign right to pursue a space program. But it is barred under U.N. Security Council resolutions from using ballistic missile technology.
Coming so soon after North Korea's fourth nuclear test on Jan. 6, a rocket launch would raise concern that it plans to fit nuclear warheads on its missiles, giving it the capability to strike South Korea, Japan and possibly the U.S. West Coast.
The United States has deployed missile defense systems that will work with the Japanese and South Korean militaries to track the launch.
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(Reporting by David Brunnstrom; Additional reporting by Ayesha Rascoe and Mark Hosenball in Washington and Ben Blanchard in Beijing; Editing by David Alexander and James Dalgleish)
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