North Korea has positioned what is believed to be a long-range missile on a launch pad, Japan's Kyodo news agency reported.
The Taepodong-2 ballistic missile has been put on a launch pad in Musudanri, Kyodo said, citing "sources close to Japan-US relations".
North Korea has said it would launch a satellite between April 4th and April 8th. Regional powers see the launch as a disguised test of its longest-range missile and a violation of UN sanctions forbidding the reclusive state from firing ballistic missiles.
North Korea has given international agencies notice of the rocket's planned trajectory that would take it over Japan, dropping booster stages to its east and west.
Analysts said the notice was given to help the North argue the rocket launch does not violate UN sanctions put in place after it test-launched a series of missiles in 2006.
Reuters