The head of the International Energy Agency has accused Russia of throttling gas supplies to Europe at a time “of heightened geopolitical tensions” implying Moscow has manufactured an energy crisis for political ends.

Fatih Birol said on Wednesday that the IEA, which represents many big fossil fuel consuming countries, believed Russia was holding back at least a third of the gas it could feasibly send to Europe, while draining Russian-controlled storage facilities on the continent to bolster the impression of tight supplies.

“We believe there are strong elements of tightness in the European gas market due to Russia’s behaviour,” Birol said. “I would note that today’s low Russian gas flows to Europe coincide with heightened geopolitical tensions over Ukraine.”