Admiral Mike Mullen said Friday that a rocket North Korea plans to launch next month has a range that could possibly reach Hawaii.
The top U.S. military officer said that while the rocket did not have a range that could reach the western coast of the U.S. mainland, it could get to Hawaii.
"In some cases, yes, they could probably get down to Hawaii," Mullen told CNN.
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Meanwhile, South Korea, the United States and Japan warned that North Korea's planned rocket launch would violate a U.N. resolution and said they would take the issue to the Security Council if the North goes ahead with it, a news report said Saturday.
North Korea says it will send a communications satellite into orbit between April 4 and 8 as part of a peaceful bid to develop its space program.
Choson Sinbo, a pro-North Korean newspaper in Tokyo, acknowledged that rocket technology could be used for military purposes but said the North was pushing ahead with its peaceful use as part of an economic development project.
But some governments suspect the North will use the launch to test technology for a long-range missile capable of striking Alaska. They have denounced the launch as a provocative move banned under a 2006 U.N. Security Council resolution prohibiting ballistic activity by North Korea, and have warned it would invite international sanctions.
"We will immediately discuss the matter at the U.N. Security Council," Japanese nuclear envoy Akitaka Saiki told reporters after talks with his U.S. and South Korean counterparts in Washington, according to Japan's Kyodo news agency.
South Korean envoy Wi Sung-lac reaffirmed Seoul's position that a North Korean rocket launch would violate the U.N. resolution "no matter what" is "on the top" of the rocket, South Korean news channel YTN reported.
North Korea has threatened unspecified "strong steps" if the Security Council criticizes the launch, and has suggested it would reverse steps made to disable its nuclear program.
Wi and Saiki held separate meetings Friday with President Barack Obama's new chief representative on North Korea, Stephen Bosworth, and with Sung Kim, another U.S. envoy who handles day-to-day dealings with the North.
"We've discussed ways to deal with (the rocket issue) at the U.N. Security Council, resume six-party talks and so on," Wi said after meeting with Bosworth and Kim for two hours, South Korea's Yonhap news agency said.
Wi declined to elaborate on how the U.N. Security Council might respond to a launch.
"We expect the Security Council action but we will not prejudge or predict the content of the action. It depends on the Security Council's decision," YTN showed Wi telling reporters.
Russia said North Korea has the right to the peaceful use of space like other countries, but urged the North to cancel the launch.
"The atmosphere on the Korean peninsula is such that the launch of a rocket would be an additional factor of instability, increasing tension," Deputy Foreign Minister Alexei Borodavkin told The Associated Press on Friday. "And so we have appealed and are appealing to our partners and friends, North Korea, to refrain from this step."
In Tokyo, Japanese Defense Minister Yasukazu Hamada on Friday ordered the military to prepare to shoot down any debris that could fall on Japanese territory if the rocket launch fails. He called on troops to mobilize interceptor missiles and has sent two warships to the Sea of Japan.
South Korea is also dispatching an Aegis-equipped Sejong the Great destroyer off the east coast to monitor the launch, a military official in Seoul said. He asked not to be identified because he was not authorized to speak to the media.
Two U.S. Aegis-equipped ships docked in South Korea — USS John S. McCain and USS Chafee — will set sail Monday, according to the U.S. military in South Korea. It declined to give further details, but South Korean media have reported the vessels will monitor the North Korean launch.
The Associated Press contributed to this report.