Countries: Non-nuclear weapon states
Highly enriched uranium
According to the 2020 IAEA Annual Report, as of the end of 2020 there were 156 significant quantities of HEU under safeguards at states with comprehensive safeguards agreements. This corresponds to about 15 tons of HEU, of which about 10 tons is HEU in spent fuel of BN-350 reactor that is stored in Kazakhstan. The amount of unirradiated HEU is estimated to be 4 MT.
Plutonium
Of the non-nuclear weapon states, Japan owns the largest stock of separated plutonium. According to its 2020 declaration, it owned 46.1 tons of the material, of which 8.9 tons were located in Japan. Other countries that own separated plutonium include Spain, Switzerland, Italy, and the Netherlands, which own civilian plutonium that is stored abroad.