Europe is at the epicentre of the first global energy crisis, the chief of the International Energy Agency (IEA) has told Euronews.
Moscow's invasion of Ukraine has compounded the crisis, prompting European countries to turn away from importing some Russian energy.
"We are in the middle of the first global energy crisis," said Dr Fatih Birol, executive director of the IEA, speaking at an energy efficiency conference in Denmark.
"It is felt everywhere around the world. But the most in Europe. Europe was the main buyer of Russian energy around the world: oil, gas, coal and others.
"And this crisis will not be over -- I'm afraid -- sometime very soon.
"As a result of that, we have to take some measures to push this crisis back. And one of the key measures is to use energy much more efficiently in the transportation sector, homes and in the industrial sector."
Dr Birol also warned a harsh winter could lead to the rationing of gas in Europe and beyond.