MOSCOW (Sputnik) — Earlier media reports had suggested that the launch of the latest version of the Proton-M rocket might be postponed from May 17 until late May or early June.
"The launch may be shifted to May 28 at the client's request," the source said.
The Proton-M, produced by Russia's Khrunichev State Research and Production Space Center, is the largest carrier rocket in the country's space launch vehicle fleet. The rocket has lifted dozens of Russian-made and foreign satellites since it was first launched in 2001.
The Proton-M rocket's phase four modernized version uses the Briz-M upper stage engine and is capable of placing satellites weighing up to 6,300 kilograms (6.9 US tons) into geostationary orbit.
The currently used Phase III Proton Briz-M version is capable of lifting satellites weighing up to 6,150 kilograms.