Fears that Europe could be engulfed by a winter energy crisis reached new heights yesterday after the Russian energy supplier Gazprom extended the shutdown of gas flows it had imposed through its key Nord Stream 1 pipeline into Germany.

The seriousness of the situation is underlined by the fact that Russia kept gas supplies to Europe flowing even at the height of the Cold War. By contrast, the pipeline has now been shut down twice since the Russian invasion of Ukraine: for 10 days in July in addition to the current indefinite closure.

Gazprom said supplies would be halted indefinitely after a leak had been detected in the pipeline and would not restart until repairs had been fully implemented. The move came hours after G7 nations had agreed to impose a price cap on Russian oil in order to stem funds for Vladimir Putin’s regime and its invasion of Ukraine.

Flows through the pipeline – which stretches from the Russian coast near St Petersburg to north-eastern Germany and can carry up to 170m cubic metres of gas a day – had been due to resume yesterday after a three-day halt.

But hours before gas was due to be pumped, Gazprom published a photo of what it said was an oil leak on a piece of Nord Stream 1 equipment.