Japan's government commission on nuclear energy has decided to reduce the country's stockpile of plutonium.
Japan has been promoting a program to recycle plutonium extracted from spent nuclear fuel.
In principle it does not possess plutonium whose purpose is unclear, because the material can be used for nuclear weapons.
But the unused stockpile keeps growing. Japan now has 47 tons of plutonium at home and abroad. If the fuel reprocessing plant at Rokkasho Village in the northern prefecture of Aomori is completed as scheduled in 2021, it will produce up to 7 tons of plutonium annually. This has heightened international concern.
The Atomic Energy Commission on Tuesday revised its guidelines on plutonium use for the first time in 15 years, stipulating that the stockpile will be reduced.
Japan currently uses plutonium for mixed oxide fuel for nuclear power plants. Under the revised guidelines, reprocessing plants are obliged to produce only the amount necessary, and what's produced must be used up. Power companies will be asked to cooperate in using and reducing plutonium.
Plutonium used for research and development, as in the Monju fast-breeder reactor, could be disposed of if there's no plan for what to do with it.
Commission chief Yoshiaki Oka said Japan must avoid being seen as stockpiling plutonium, amid global efforts toward nuclear nonproliferation. He stressed the need to specify how plutonium is used.