FRANKFURT- The chief executive of German utility E.ON on Tuesday said Europe's sustainable finance taxonomy threatens plans for new gas-fired power generation plants, which are meant to help back up networks when renewable power is too volatile.

"If the legal framework conditions stay the way they are, plans for gas plants will become difficult," Leonhard Birnbaum said at the annual Handelsblatt Energy Summit. "And if we don't build gas plants, coal-to-power plants will have to run longer."

Experts will supply more feedback on the controversial plans by Jan. 21, with green lobbyists fearing too much tolerance for nuclear and gas while traditional utilities warn of possible gaps of stable electricity supply. 

(Reporting by Vera Eckert Editing by Madeline Chambers) ((; +49 30 2201 33654; @EckertVera;))