A new head-end process step and feasibility study of the process for an operating reprocessing plant, consisting of electrolytic-disassembly cutting and simultaneous lixiviation of metal-clad oxide power-reactor fuels, has been developed and its potential as a fuel head-end reprocessing step for stainless steel and Zircaloy-clad oxide fuels evaluated with unirradiated fuels. The electrolytic cutting and simultaneous lixiviation is realized by the penetration into each of the fuel rods of the assembly, of a layer of hollow, insulated metallic needles by anodic dissolution of a small slit of the fuel cladding by the electrolyte under high pressure, which by its action simultaneously lixiviates the oxide from the fuel rods; the fuel assembly acts as the anode and the needle layer as the cathode.