Abstract: The present invention relates to a process for removing rare earth elements (RE) from spent nuclear fuel. The spent nuclear fuel is subjected to an oxidation step at a temperature of between about 200.degree. to about 800.degree. C. and a heating step at a temperature of between about 1000.degree. C. to about 1600.degree. C. The process results in the segregation of the spent fuel into a rare earth-rich fluorite-type phase and a rare earth-poor U.sub.3 O.sub.8 phase. The RE-rich fluorite type phase is separated from the RE-poor U.sub.3 O.sub.8 phase by conventional separation techniques such as sieving, air classification, sedimentation and the like.