Washington has been pressing Tokyo to return over 300 kilograms of mostly weapons-grade plutonium given to Japan for research purposes during the Cold War era, Japanese and U.S. government sources said Sunday.
U.S. President Barack Obama’s administration, which is keen on ensuring nuclear security, wants Japan to return the plutonium supplied for use as nuclear fuel at a fast critical assembly in Tokaimura, Ibaraki Prefecture, the sources told Kyodo News.
The highly concentrated plutonium could be used to produce 40 to 50 nuclear weapons.
Japan has strongly resisted returning the plutonium, which it says is needed for researching fast reactors. But it has finally given in to repeated U.S. demands, the sources said.
At present, Japan has another estimated 44 tons of plutonium, but its quality is not on par with the plutonium used for research purposes, a Japanese expert said.
Since a nuclear crisis broke out in Japan in March 2011, the United States has expressed its concern to the Japanese government over how it will use plutonium.
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