BERLIN, May 19 (RIA Novosti) - Without new supply routes from Russia, Europe will struggle to receive the additional 80-100 billion cubic meters of gas it will need by 2020, a top official at Russian energy giant Gazprom said on Tuesday.

"Those European politicians, who are trying to block Russia's construction projects for new gas pipelines, bear great responsibility," the Gazprom Deputy CEO Alexander Medvedev told an annual gas cooperation conference between Russia and the European Union, which began in Berlin on Tuesday.

"Without the diversification of gas supply routes to Europe, it will not receive the additional 80-100 billion cubic meters of gas from Russia that it will need by 2020," he said.

"It isn't Gazprom, but Russophobe politicians are a real threat to Europe's energy security," Medvedev said.

He added that a link between Europe's energy security and Russian gas supplies was "fictitious and politicized."

Russia is Europe's largest gas supplier, providing Europe with about a quarter of its overall gas demand. It is closely followed by Norway (18%) and Algeria (10%).