In July 1960, Mikhail Yangel's OKB-586 design bureau, based in the city of Dnepropetrovsk Ukraine proposed the development of a rocket capable of carrying 40 tons into low Earth orbit, filling the gap between Korolev's N-1 (75 tons) and Chelomei's UR-500 (20 tons). Named R-56 with industrial designation 8K68, its preliminary design saw the liftoff weight increased from 1,200 to 1,400 tons.

On May 22, 1963, the Central Committee of the Communist Party and the Soviet of Ministers of the USSR authorized the experimental project (EP) for the R-56 rocket. Its potential applications included delivering geostationary satellites, lunar and planetary probes, manned circumlunar expeditions, and lunar surface supply missions.

During conceptual design, KB Yuzhnoe explored three configurations for the R-56:

Four-module: Each module with a 3.8-meter diameter for rail transportation.
Seven-module: Each module with a 3-meter diameter, similar to the R-36 missile.
One-module: Booster stages with a 6.5-meter diameter, necessitating waterway transportation.
Despite the need for significant upgrades to production facilities and new means of stage delivery from manufacturer to launch sites in Dnepropetrovsk, KB Yuzhnoe chose the one-module configuration.