The European Commission president has warned EU member states not to backtrack on their long-term drive to cut fossil fuel use, as Germany, Austria and the Netherlands said they would fire up coal plants after Russia moved to limit gas supplies.

Ursula von der Leyen said governments need to stay focused on “massive investment in renewables”.

“We have to make sure that we use this crisis to move forward and not to have a backsliding on the dirty fossil fuels,” she said in an interview. “It’s a fine line and it’s not determined whether we are going to take the right turn.’

Countries are concerned about further cuts to gas supplies, which EU leaders claim have been orchestrated by the Kremlin

The imminent rise in coal use, even if temporary, has stoked concerns that European countries could use the crisis to delay the switch to less-polluting alternatives.

Rob Jetten, the Netherlands’ climate and energy minister, on Monday said the country would change laws that require coal-fired stations to operate at a maximum of 35 per cent capacity.

Germany and Austria announced the emergency restart of mothballed coal plants on Sunday after Russia cut capacity on the Nord Stream 1 pipeline by 60 per cent last week. The pipeline, which runs through the Baltic Sea to

Germany is one of the main conduits for Russian gas to Europe. EU officials are concerned Moscow could cut supplies further before winter.

Russia has blamed the capacity cut on technical issues affecting the pipeline. However, it has declined to make up the shortfall through other pipeline routes.