Japan submitted to IAEA its annual declaration of holdings of civilian plutonium as of December 31, 2009 - INFCIRC/549/Add.1/13.
According to the document, at the end of 2009 Japan had 4,400 kg of separated unirradiated plutonium at the reprocessing facilities, 1,900 kg in unirradiated MOX fuel, and 3,300 kg in the MOX fuel manufacturing process. Additional 400 kg of unirradiated plutonium is "held elsewhere." In addition, Japan has unirradiated plutonium outside of its territory - the amount of that material is declared as 24,100 kg of "fissile plutonium."
Japan also declared 120,000 kg of plutonium contained in spent fuel held at reactors sites and 24,000 kg - in spent fuel at reprocessing facilities. Some material, less than 500 kg, is declared as held at other sites.
Earlier, the Japan Atomic Energy Agency detailed plans regarding 3.1 tonnes of "fissile plutonium" that it has in its possession.