[en] A method is described of producing durable coherent compacts of particulate ceramic nuclear fuel which imparts lasting plasticity to the particulate ceramic material. The method consists of: providing an aqueous solution of a diamine and adding a source of oxalate ions to the diamine aqueous solution whereby the high pH of the solution due to hydrolysis of the diamine dissolves the source of oxalate ions, then adding the aqueous solution of diamine and dissolved oxalate ions to particulate nuclear fuel material comprising uranium dioxide, and blending the solution containing diamine and oxalate ions therethrough to produce a fugitive binder for the fuel material; and pressing the resultant blend comprising particulate fuel material and diamine with oxalate ions into a coherent compact