Although North Korea shut down its reactor at its nuclear complex at Yongbyon, it fabricated centrifuges with enriched uranium at a new facility on the same site, a commentary published in the Asia Times said Monday.
David Albright, president of the Institute for Science and International Security in Washington, said it appears North Korea, which recently unsuccessfully tried to launch a rocket, is "preparing for a third nuclear test."
Albright said the device could be one of the dozen plutonium devices already built, or one of highly enriched uranium or possibly a plutonium device sheathed by uranium.
A South Korean observer recently told The New York Times a uranium test would make "the entire affair far more dangerous from the non-proliferation point of view."
Senior Chinese and North Korean officials met Saturday in Beijing, eight days after the North's controversial missile launch.
North Korea's Korean Central News Agency called the meeting between Kim and Wang a "strategic dialogue" in which they "exchanged views on further developing the friendly and cooperative relations between the two parties and two countries and matters of mutual concern," the Asia Times said.
China made a rare move against its traditional ally last week in joining a U.N. Security Council condemnation of North Korea's plans to launch a ballistic missile. The rocket exploded less than 2 minutes after takeoff April 13. Reports later surfaced that North Korea was considering a third underground nuclear test.
North Korea said the project was to send a satellite into orbit, but a majority of U.N. members expressed doubts and said it was a cover for testing ballistic missile technology.