Belgium submitted to IAEA a declaration of its civilian plutonium holdings as of December 31, 2010 - INFCIRC/549/Add.3/11. According to the document, at the end of 2010 Belgium had no unirradiated separated plutonium stored at reprocessing plants and no separated plutonium held abroad. It also had less than 50 kg of the material in each of the following categories - held up in the fuel fabrication process, in unirradiated MOX fuel, and "held elsewhere." These numbers has not changes since the 2009 declaration.

According to the declaration, Belgium has an estimated 34 tonnes of plutonium in irradiated fuel of power reactors, up from 33 tonnes in 2009.