North Korea has positioned a Taepodong-2 missile on the launch pad at its facility in Musudan in the east of the country, U.S. officials told NBC News on Wednesday.
Speaking in Mexico City, Secretary of State Hillary Rodham Clinton called it a "provocative act" that would have consequences.
Clinton told reporters that the U.S. believes a North Korean plan to fire a missile for any purpose would violate a resolution by the U.N. Security Council. She said the U.S. would raise the issue with the United Nation if the plan went forward.
Pyongyang has said it intends to use the missile to launch a satellite into space. The North Koreans issued an international notice that the launch may occur sometime between April 4-8.
According to the U.S. officials, while two stages of the missile can be seen, the top is covered with a shroud supported by a crane.
But now that the missile is on the pad, the launch itself could come within a matter of days, a likelihood that has sparked a flurry of diplomatic activity as the event would be in violation of a U.N. ban prohibiting the country from ballistic activity. Some fear the launch is a cover for the test-fire of long-range missile technology.
North Korea has described the pending launch a "peaceful space launch," but U.S. officials and experts say it would employ the very same technology used to launch ballistic missiles, and if successful it would be the first proof that North Korea would have the ability to launch a ballistic missile against at least Alaska or Hawaii.
U.S. warningsDirector of National Intelligence Dennis Blair testified before Congress that a successful test of a three-stage rocket would demonstrate North Korea's ability to reach the continental United States with a ballistic missile.
The commander of U.S. Pacific Command, Adm. Timothy Keating, warned recently that the U.S. has the ability to shoot down the missile should it threaten either the United States or its allies, but Pentagon and military officials believe that scenario is highly unlikely.
Japan, on the other hand, has said it is prepared to shoot down the missile with its Patriot anti-missile defense systems acquired from the United States.
The last such test of a Taepodong-2 in 2006 was a spectacular failure when the missile started to cartwheel almost immediately after liftoff and was either destroyed by ground controllers or simply flew apart from the centrifugal force.
Flurry of talksSouth Korea's chief nuclear envoy, Wi Sung-lac, said Wednesday after returning from talks with his Beijing counterparts that a launch would trigger a response.
"If North Korea launches rocket, certain countermeasures are unavoidable," he said. He refused to elaborate, saying the measures, including any sanctions, would be discussed among U.N. Security Council member nations.
Yonhap quoted an unnamed intelligence official Monday as saying authorities "strongly believe" the launch will take place April 4-5 and believe it will involve a long-range missile — not a satellite.
It probably won't be clear if the latest launch is a satellite or a missile test until footage can be analyzed after the event; the trajectory of a missile is markedly different from that of a satellite.
Analysts have been watching for signs of a satellite or missile on the launch pad in Musudan. Satellite imagery from March 16 showed progress toward mounting a rocket, with a crane hovering over the launch pad, said Christian LeMiere, an editor at Jane's Intelligence Review in London.
He said that once mounted, scientists would need at least a week to fuel and carry out tests before any launch. Images from earlier this month did not indicate the rocket or missile had been mounted, he said Wednesday.