MOSCOW, May 28. /TASS/. Russian gas supplied to Europe via the Nord Stream has a carbon footprint that is four times smaller than from the US gas, Russian Deputy Prime Minister Alexander Novak told reporters.

"Russian gas supplied to Europe via the Nord Stream, according to various analytical and consulting agencies, has almost 4 times smaller carbon footprint per kWh than gas supplied to Europe from the United States. This is mainly due to the fact that in the United States, most of the gas is produced from shale rocks using hydraulic fracturing", Novak explained.

According to him, Russia pays great attention to ensuring its environmental leadership. US Energy Secretary Jennifer Granholm on Thursday argued that natural gas produced in Russia is allegedly the "dirtiest" in the world.

US liquefied natural gas (LNG) is produced using shale natural gas by fracking which is one of the most non-environmentally friendly methods in the industry, and then piped to factories for further liquefaction. Then LNG is transported by tankers to Europe, which additionally significantly increases the total greenhouse gas emissions throughout the life cycle of the US LNG.