The US defense department was closely monitoring the prospect of a satellite launch this month by North Korea, a top Pentagon official said.
George Little, acting assistant secretary of defence for public affairs, said the US was "monitoring it closely. We understand the impact it could have on regional stability".
"We're working very closely with our Republic of Korea (South Korea) allies as well as our Japanese allies to monitor. We hope it doesn't happen. But if it does, we'll be ready to track it," Little was quoted as saying by Xinhua.
"I believe we have what we need to track (the launch) and to also work closely with our allies in the region to respond," he added.
Little said North Korea would be "violating UN Security Council resolutions if they move ahead with such a launch".
He called upon Pyongyang not to go ahead with the launch, but said the Pentagon was operating on the assumption that the launch could happen.
North Korea has indicated that it intends to launch the satellite, he noted. "They have done so in the past. So if history is any guide to the future, we would be remiss if we didn't take those announcements for what they are."
North Korea has said it would launch the Kwangmyongsong-3 satellite between April 12 and 16 to celebrate the centenary of the birth of late leader Kim Il Sung.