Development of the rocket, the fifth-generation Long March-5 launch vehicle of the Long March family, has entered a "runoff" phase, according to the State Administration of Science, Technology and Industry for National Defence.
The rocket will have a payload capacity of 25 tonnes to low Earth orbits, or 14 tonnes to geostationary transfer orbit, about twice the current capacity.
The would-be capacity will be equivalent to that of mainstream carrier rockets now in use around the world.
The Long March rocket family has completed more than 200 missions since 1970, when a Long March-1 rocket sent China's first satellite, Dong Fang Hong 1, or "the East is Red", into Earth orbit.
