The missile, believed to be a long-range Taepodong-2, would be launched from North Korea's Dongchang-ni site on the northwestern coast, said the Yomiuri daily, Japan's top-selling newspaper. It cited an analysis by the Japanese Defence Ministry and intelligence gathered by US reconnaissance satellites.

The missile launch could come between July 4 and 8, the paper said. It noted North Korea had fired the Taepodong-2 missile on July 4, 1996. Also July 8 is the anniversary of the 1994 death of North Korea founder Kim Il Sung.

The Yomiuri report is the latest in mounting media speculation that the communist country could launch a long-range missile soon following its underground nuclear test on May 25.

A spokesman for the Japanese Defence Ministry declined to comment on the report. Officials from South Korea's Defence Ministry and the National Intelligence Service - the country's main spy agency - said they could not confirm it.

While the Yomiuri speculated the Taepodong-2 could fly over Japan and toward Hawaii, it said the missile would not be able to hit the main islands of Hawaii.

In Washington on Tuesday, General James Cartwright, vice chairman of the Joint Chiefs of Staff, said it would take at least three to five years for North Korea to pose a real threat to the West Coast of the United States.

North Korea is believed to have enough weaponised plutonium for at least half a dozen atomic bombs. The regime revealed last week that it is also producing enriched uranium. The two materials are key ingredients for making atomic bombs.

North Korea conducted its second nuclear test on May 25 following its first underground atomic blast in October 2006. -- AP