The energy crisis has already cost the 27-nation bloc more than 22 billion euros ($26 billion) in higher fossil fuel bills, von der Leyen said after a meeting of the EU's top executive body dedicated to the issue.

"These events make clear we are paying a very high price for our over dependency on fossil fuels," the European Commission chief told a press conference in Brussels, calling for a faster switch towards renewables and nuclear power.

"We need to scale up the homegrown, affordable, reliable energy," she said, adding the commission was hoping to get new rules aimed at accelerating grid connections across the bloc and present an "electrification strategy" before the summer.

Oil and gas prices have surged since US-Israeli strikes on Iran began on February 28, with Tehran retaliating by effectively blocking the strategically vital Strait of Hormuz and attacking Gulf energy infrastructure.

To address the cost crunch, the commission is considering relaxing its state aid rules to give member states more space to support the "most exposed sectors", von der Leyen said.

Details are to be unveiled as part of a package to be presented next week before an informal meeting of European Union leaders in Cyprus, she added.

The commission later said it was consulting member states on a draft proposal that would allow governments to grant "calibrated temporary support" to affected sectors.

This would include enabling states to "cover part of the price increases for fuel or fertilisers", it said.

Upping the share of electricity costs that state aid could cover for energy-intensive industries was also on the table, the commission said.

Von der Leyen said the EU was looking to coordinate oil stock releases and the filling of gas storage across the bloc to avoid member states competing against each other on the market, driving up prices.

Steps to support energy efficiency are also being considered, the commission president added, citing the "renovation of buildings" and "the renewal of equipment in industrial operations" without further elaborating.

"The least expensive energy is the energy that is not used," she said.

A proposal to reform electricity taxes and grid charges will follow in May, von der Leyen added.