SEOUL, South Korea — North Korea appears to be preparing to test an advanced missile designed to reach the United States, a U.S. official said Monday, ratcheting up tensions after its second underground nuclear test.
The regime, which last month raised tensions worldwide by conducting a nuclear test, could fire its missile June 16, when South Korean President Lee Myung-bak meets with President Barack Obama in Washington, according to South Korean reports.
The reclusive communist country also reportedly has bolstered its defenses and conducted amphibious assault exercises along its western shore, near disputed waters where deadly naval clashes with the South have occurred in the past decade.
Satellite images and other intelligence indicate that the North has transported its most advanced long-range missile to the new Dongchang-ni facility near China, South Korea's Yonhap news agency reported.
A U.S. official confirmed the Yonhap report and said the missile was moved by train, although he did not comment on where it was moved to, and he said it could be more than a week before Pyongyang is ready to launch it. He spoke on condition of anonymity because the issue involves intelligence.
The activity at the launch site came as the U.N. Security Council mulled punitive action for North Korea's May 25 nuclear test, and ahead of the June 16 summit in Washington between Lee and Obama.
Complicating the situation further, a trial of two U.S. journalists is set to begin Thursday in Pyongyang. Laura Ling and Euna Lee are accused of entering the country illegally and engaging in "hostile acts."
U.S. Defense Secretary Robert Gates, visiting Manila in the Philippines, said that although North Korea does appear to be working on its long-range missiles, it is not yet clear what its plans are for them.
Gates added that the "30 interceptors we have are adequate for years to come to deal with the North Korean threat as we see it developing." If North Korea were to expand its capabilities, the United States would have "ample time" to build additional interceptors, he said.
President Lee, hosting a conference of Southeast Asian leaders on the southern island of Jeju, warned in his weekly radio address that the South would "never tolerate" military threats.
Lee Sang-hyun, director of the Security Studies Program at the Sejong Institute in Seoul, said the North's moves have been calculated to get international attention.
"North Korea wants to become a full nuclear state, then negotiate," he said. "As a nuclear state, it will have more to gain from the U.S."
Tensions also increased off the Koreas' western coast.
South Korean coast guard ships were escorting fishing boats near the island of Yeonpyeong, and Yonhap reported that North Korean troops conducted amphibious assault maneuvers, along with training on speedboats, that could be preparations for skirmishes at sea.