[en] An experimental system was developed for measuring the high-temperature creep rates of ceramic nuclear fuels to temperatures near their melting points. The results of a series of experiments carried out on UO₂ at temperatures above 2400⁰C are reported. The strain rate was found to be proportional to the 5.7 power of the stress while activation energies ranged from 250 to 340 Kcal/mole. An expression for describing the primary creep was derived from the initial time dependence of the deformation after stress application. A technique for studying the hot pressing behavior at 2580⁰C was devised but no definitive results were obtained from the first series of experiments. An empirical relationship is proposed for calculating the creep rates at very high temperatures