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 2019.
Japan (INFCIRC/549/Add.1-23) reported owning the total of 45.5 tons of plutonium, 8.9 tons of which is in Japan (the numbers in 2018 were 45.7 tons and 9.0 tons respectively). According to the Status Report on Plutonium Management in Japan - 2019 released in August 2020, out of the 36.6 tons of plutonium abroad, 21.180 tons are in the United Kingdom and 15.435 tons are in France.
Germany (INFCIRC/549/Add.2-23) 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.3-19) 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 2018.
Switzerland (INFCIRC/549/Add.4-24) 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.5-24) reported having 90.2 tons of separated unirradiated plutonium in its custody. Of this amount, 15.5 tons belongs to foreign countries. It appears that all that plutonium - 15,435 kg - belongs to Japan. The amount of plutonium owned by France is 74.7 tons, an increase of 7 tonnes from previous year (67.7 tons).
China has not has not submitted its 2017-2019 reports as of 20 January 2021. 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.8-23) reported owning 115.8 tons of separated plutonium, the same as in 2018. In addition to that, the United Kingdom stores 24.1 tons of foreign plutonium (of which 21.8 tons is owned by Japan). The amount of foreign plutonium increased by 1 ton.
Russia (NFCIRC/549/Add.9-22) reported owning 63 tons of civilian plutonium, an increase of 1.7 tons from 2018.
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 (an increase from 0.32 tonnes in 2018), 0.94 tonnes of HEU in irradiated research reactor fuel, and 0.01 tonnes in the category "HEU held elsewhere."
France declared 5373 kg of HEU (5144 kg in 2017), of which 3836 kg (3654 kg) is unirradiated material - 930 kg (996 kg) of HEU at fuel fabrication or reprocessing plants, 51 kg (101 kg) at civil reactor sites, 2855 kg (2517 kg) at various research facilities. Also declared are 1537 kg (1530 kg) of irradiated HEU - 99 kg (91 kg) at civil reactor sites and 1438 kg (1439 kg) in other locations.
The United Kingdom reported having 734 kg of HEU (742 kg in 2018). Of this amount, 598 kg is unirradiated HEU: less than 1 kg of unirradiated HEU is stored at the enrichment plants, less than 1 kg is at civil reactor sites, 417 kg - at fuel fabrication facilities, and 181 kg - at other sites. Irradiated HEU is located at civil reactor sites (5 kg) and other sites (132 kg).