The head of a global trade association said on Tuesday that airline passengers will face higher ticket prices as the industry moves towards its goal of reducing emissions to net zero.
Willie Walsh is the director general of the International Air Transport Association, which includes most of the world's big airlines.
Higher prices for fossil-based jet fuel have led to an increase in air fares.
Walsh told reporters at an annual media briefing that the industry cannot absorb the increases they have seen.
As the industry transitions to net zero, there needs to be an impact on ticket prices. Increased costs can't be absorbed by the airlines.
Environmental groups say that higher air travel costs will help to curb emissions.
Walsh praised efforts by the US to lift output of clean fuels, despite European objections that new American incentives could create an even playing field.
Walsh said that sustainable aviation fuels are part of the answer in the US.
He didn't like the EU's moves to make airports give more supplies of SAF. He said that Europe's answer to the problem makes people feel bad.
In July, the European parliament backed rules on aviation fuel that set binding targets for the replacement of kerosene with lesspolluting sources, while extending the definition of a green fuel.
In the US, the Biden administration has launched a government challenge to supply at least 3 billion gallons of SAF a year.
Fuel for flights can't be replaced with other kinds of power, which makes the airline sector one of the hardest to decarbonise.
European industry leaders, including the head of the aircraft maker, say the legislation is unfair because it includes subsidies to the SAF industry.
Global airlines are expected to make $4.7 billion in combined profits in 2023, which would be the first industry-wide profit in over a year.