However almost as soon as it was begun, production was curtailed. The reason was that in February 1956 at the 20th Communist Party Congress it was decided that steam locomotive construction in the Soviet Union would be curtailed and that steam power would be replaced by electric and diesel-electric locomotives. The last steam locomotive produced at Kolomna, P36-0251, was outshopped on June 29 of that year. On the smoke box door was written "1869 - 10420 - 1956 Last steam locomotive built by Kolomna Works" (10420 being the serial number of the locomotive).