Spent nuclear fuel is added to an electro-reduction cell, wherein the electro-reduction cell includes a halide salt electrolyte, and anode, and a cathode including an alloy of uranium and a first metal forming a low melting point alloy with uranium, the first metal being one or more of: iron; chromium; nickel; manganese; and cobalt. The spent nuclear fuel is electrochemically reduced at a potential sufficient to reduce plutonium and lanthanides in the spent nuclear fuel, to form a molten alloy of the first metal, uranium and higher actinides present in the spent nuclear fuel. The alloy is extracted from the electro-reduction cell while uranium oxide is present in the electro-reduction cell. The spent nuclear fuel includes uranium oxide and at least 1 mol of lanthanides per tonne of uranium in the spent nuclear fuel, and the electro-reduction cell is operated at a temperature above the melting point of the alloy.