“Not to push the energy efficiency measures is another way of asking for higher emissions, higher energy import bills and higher energy insecurity," Birol said.

"So, therefore I think it is a must that we all have to push the energy efficiency measures throughout the energy supply chain,” he said. “Europe being a champion of climate change [policies], it needs also to be a champion of energy efficiency.”

Fossil fuel subsidies 'absurd'

Energy imports cost the EU €84 billion in 1999 and rose rose nearly sixfold in the past decade, hitting €488 billion last year, figures from the EU's statistical office Eurostat show.

“On the one hand, not to use energy efficiently and on the other hand to – in some countries – subsidise fossil fuel energy is an absurd strategy,” the IEA economist said.