[en] Main reasons and results of transition to utilization of uranium-erbium fuel (UEF) at the Leningrad, Kursk and Smolensk NPPs are presented. It is shown that UEF using permits to regulate the steam reactivity coefficient, to modernize the control rods, to decrease the core power strength, to increase the fuel assembly reliability and burnup depth and to decrease the spent fuel volumes. Prospects of improving the UEF for the RBMK-1000 reactors are described