Europe, which receives a third of its gas supplies from Russia, has seen energy prices soaring to record highs as economies come back online after the end of pandemic lockdowns.
Critics in Western capitals have blamed Russia for the price hikes, saying Moscow is not upping deliveries to pressure Europe to agree more long-term contracts and for the certification of the controversial Nord Stream 2 pipeline to Germany.
President Vladimir Putin in late October instructed Gazprom to increase supplies to Europe after it finished filling Russian storage facilities by November 8.
"Gazprom has approved and begun implementing the plan for injecting gas into five European underground storage facilities," the company said on its Telegram channel, without specifying if gas deliveries had already begun.
"The volumes and routes of gas transportation have been determined," is said.