BRUSSELS - The European Parliament on Thursday backed landmark rules on aviation fuel that set binding targets for the replacement of kerosene with less polluting energy sources, but extended the definition of what a green fuel could be.

The requirements, which if approved would be a world first, were originally proposed by the European executive commission last year to cut the climate impact of the aviation sector, which is deemed responsible for up to 3% of global emissions.

Under the approved text, suppliers would be required to blend a minimum of 2% of sustainable aviation fuel (SAF) into their kerosene from 2025, rising to 85% in 2050 - more ambitious than the target of 63% by 2050 originally proposed by the Commission.

Under the terms of the Commission's original proposal, SAF would include bio-based fuels obtained from recycled waste and, on a smaller scale, hydrogen-based synthetic or e-fuels produced from renewable energy sources.

But the version of the rules approved by the European Parliament extended the Commission's original definition of SAF, adding recycled carbon fuels produced from waste-processing gas, and biofuels produced from animal fats or distillates.

Before the vote, EU energy commissioner Kadri Simson had urged lawmakers not to extend the definition of SAF, and to be careful with excessively ambitious targets.

Green lawmakers managed to amend the text at the last minute to exclude the use of food crops and palm oil as SAFs, which would have been permitted under exceptional circumstances in the text initially prepared by the Parliament.

The rules will now be put forward for approval by member governments and the EU Commission.

(Reporting by Francesco Guarascio; Editing by Jan Harvey)