This post contains a summary of INFCIRC/549 reports by the countries that submit annual civilian plutonium declarations that reflect the status of civilian plutonium stocks as of 31 December 2021. The total amount of plutonium declared as civilian was about 360 tonnes, an increase of about 5 tonnes since the end of 2020. Only about 130 tons of this material are under international (IAEA or Euratom) safeguards. The other 230 tonnes are not safeguarded, but are covered by various obligations not to use the material for military purposes.
Japan (INFCIRC/549/Add.1-25) reported owning the total of 45.8 tons of plutonium, 9.3 tons of which is in Japan (the numbers in 2020 were 46.1 tons and 8.9 tons respectively). According to the Status Report on Plutonium Management in Japan - 2021 released in July 2022, out of the 36.5 tons of plutonium abroad, 21.780 tons are in the United Kingdom and 14.760 tons are in France.
Germany (INFCIRC/549/Add.2-25) reported having no separated plutonium in the country for the second year in a row. Germany does not report separated plutonium outside of the country. It is believed to be less than 1 ton.
Belgium (INFCIRC/549/Add.3-21) declared no separated plutonium in storage or at reprocessing plants and "not zero, but less than 50 kg" of separated plutonium in other categories. It reported that it had no foreign plutonium as of 31 December 2021.
Switzerland (INFCIRC/549/Add.4-26) reported having less than 2 kg of plutonium in the country (in the "located elsewhere" category). The number has not changed since 2016 (it was "less than 50 kg" in 2015).
France (INFCIRC/549/Add.5-26) reported having 99.9 tons of separated unirradiated plutonium in its custody. Of this amount, 15 tons belongs to foreign countries. It appears that almost all that plutonium - 14,760 kg - belongs to Japan. The amount of plutonium owned by France is 84.9 tons, an increase of 5.4 tonnes from previous year (79.5 tons).
In its 2021 report (INFCIRC/549/Add.6-24) declared 49.4 tons of separated plutonium, of which 4.6 tons are in MOX fuel and 44.8 tons are "held elsewhere" (most of this material is believed to be in weapon components). This amount was reported to be 44.7 tons in 2018, but went back to 44.8 tons in 2019 (as indicated by the "previous year" number in the 2020 declaration). These changes appear to reflect changes in the accounting for the material - the amount reported as "disposed as waste" was 4.6 tons in 2018, but was reverted to 4.5 tons in 2020.
China has not has not submitted its 2017-2021 reports as of 27 January 2023. The last INFCIRC/549 report submitted to the IAEA showed 40.9 kg of separated plutonium as of 31 December 2016.
The United Kingdom (INFCIRC/549/Add.8-25) reported owning 116.5 tons of separated plutonium, an increase from 116.1 in 2020. In addition to that, the United Kingdom stores 24.1 tons of foreign plutonium (of which 21.780 tons is owned by Japan).
Russia (INFCIRC/549/Add.9-24) reported owning 63.5 tons of civilian plutonium, an increase of 0.1 tons from 2020.
In addition to reporting plutonium stocks, some countries also submit data on their civilian HEU:
Germany reported 0.35 tonnes of HEU in research reactor fuel, 0.94 tonnes of HEU in irradiated research reactor fuel, and 0.01 tonnes in the category "HEU held elsewhere." None of the numbers have changed since 2020.
France declared 5313 kg of HEU (5319 kg in 2020), of which 3760 kg (3785 kg) is unirradiated material - 804 kg (852 kg) of HEU at fuel fabrication or reprocessing plants, 60 kg (74 kg) at civil reactor sites, 2896 kg (2859 kg) at various research facilities. Also declared are 1553 kg (1533 kg) of irradiated HEU - 62 kg (79 kg) at civil reactor sites and 1491 kg (1454 kg) in other locations.
The United Kingdom reported having 734 kg of HEU (737 kg in 2020). Of this amount, 598 kg is unirradiated HEU (601 in 2020): less than 1 kg of unirradiated HEU is stored at the enrichment plants, less than 1 kg is at civil reactor sites, 420 kg - at fuel fabrication facilities, and 178 kg - at other sites (421 kg and 180 kg respectively in 2020). Irradiated HEU is located at civil reactor sites (5 kg) and other sites (132 kg).