In the most explicit statement of allied goals for making North Korea nuclear-free, the three governments have agreed the North should not be allowed to use nuclear energy even for peaceful purposes as long as Kim Jong-il remained in power, the Yomiuri Shimbun said.

"As long as there is fear that North Korean facilities might be used for military purposes, we can't tolerate any nuclear facilities, not even those operated for peaceful purposes," Yomiuri quoted a senior Foreign Ministry official as saying.

North Korea, believed by the United States to already have one or two nuclear bombs, has sparked global alarm over its nuclear ambitions.

The Yomiuri Shimbun, quoting Japanese government sources, said the United States, Japan and South Korea would only consider giving aid to the North to build thermal power plants.

An agreement to rid North Korea of all nuclear programs was reached after talks among officials from the three countries, it said.

Japanese Foreign Ministry officials were not immediately available for comment.

South Korea's Ministry of Foreign Affairs and Trade declined to confirm the report.

"It would be inappropriate for us to comment on any details as we're still in negotiations. We would like to keep our cards hidden."

The report comes ahead of an expected visit next week to North Korea by two US groups, who might tour the nuclear complex at Yongbyon, which Washington believes is at the heart of North Korea's suspected nuclear arms program.