The Progress Rocket and Space Center within the federal space agency Roscosmos submitted the conceptual design of the Amur methane-powered carrier rocket with a reusable stage to the space industry’s research institutes, the Progress press office told TASS on Tuesday.

"The sketch of the Amur-LNG space rocket system is currently undergoing an expert study at leading research institutes of the space industry," the press office informed.

Most research institutes have issued positive conclusions for the conceptual design, the Progress Rocket and Space Center specified. The space firm did not rule out that the timeframe of developing the new methane-powered rocket might be extended.

"The Progress Rocket and Space Center does not rule out that the final date of delivering the conceptual design may be altered, considering the need to finalize it," the press office said.

The project may be finalized and improved, considering the principal customer’s additional proposals on involving [Russian energy giant] Gazprom and its organizations in the project and the survey works carried out in advance at the Vostochny Cosmodrome, the Progress press office explained.