A method for preparing a powder including one or more oxides selected from uranium oxide UO.sub.2, plutonium oxide PuO.sub.2 and minor actinide oxides, the minor actinides being selected from americium, neptunium and curium, including steps of: a) cryogenic granulation of an aqueous solution comprising cations selected from uranium-based cations, plutonium-based cations, and minor actinide-based cations; b) freeze-drying the granules obtained in a); and c) calcining the granules obtained from b). The method can be used to manufacture nuclear fuels or blankets charged with minor actinide(s).

A method for preparing a powder including one or more oxides selected from uranium oxide UO.sub.2, plutonium oxide PuO.sub.2 and minor actinide oxides, the minor actinides being selected from americium, neptunium and curium, including steps of: a) cryogenic granulation of an aqueous solution comprising cations selected from uranium-based cations, plutonium-based cations, and minor actinide-based cations; b) freeze-drying the granules obtained in a); and c) calcining the granules obtained from b). The method can be used to manufacture nuclear fuels or blankets charged with minor actinide(s).