The Russian government has effected an energy crisis to gain political leverage, says International Energy Agency Executive Director Fatih Birol in an interview with Financial Times.

Russia is throttling the flow of gas at a time of "heightened geopolitical tensions," states Birol.

"I would note that today's low Russian gas flows to Europe coincide with heightened geopolitical tensions over Ukraine," he says.

Many EU nations are complaining of a lack of gas stockpiles, which has driven up gas prices.

Birol assumes that Russia is withholding at least a third of the gas usually sold to Europe. At the same time, inventories in Europe controlled by Russia are being drained.

"We believe there are strong elements of tightness in Europe' gas markets due to Russia's behavior," he says

"Russia could increase deliveries to Europe by at least a third, this is the key message."

For a long time, Russia has maintained that long-term gas supply contracts with Europe have been honored. But critics say that the country has withheld vital gas supply by limiting gas sales on the spot markets.

Meanwhile, Russia has mobilized 100,000 soldiers on the border to Ukraine, sparking fears of an invasion of the country.

The US and the EU have threatened to impose extensive sanctions in the event of an invasion.

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