The cost of decarbonising air travel is likely to push up ticket prices and put some off flying, a group representing the UK aviation industry says.
Measures such as moving to higher-cost sustainable aviation fuel will "inevitably reduce passenger demand", according to Sustainable Aviation.
But it found people will "still want to fly" despite "slightly higher costs".
Annual passenger numbers are still expected to rise by nearly 250 million by 2050, it added.
Sustainable Aviation is an alliance of companies including airlines such as British Airways, airports such as Heathrow and manufacturers like Airbus.
It said that sustainable aviation fuel (Saf) would be a key part of the industry's "journey to net zero", accounting for at least three quarters of the fuel used in UK flights by 2050.
Saf is produced from sustainable sources such as agricultural waste and reduces carbon emissions by 70% compared with traditional jet fuel.
However, it is currently several times more expensive to produce - costs the group says would have to be passed on.
The cost of using carbon offsetting schemes to reach net zero will also drive up airlines' costs, the report adds.
Heathrow Airport's director of sustainability Matthew Gorman - who chairs Sustainable Aviation - said this "green premium" will have "some impact on future demand" for air travel.
But he added that the industry could still "grow significantly" as most people were "happy to pay a bit more to travel".
The Sustainable Aviation group argues the move to greener travel presents a big opportunity for the UK, which has the world's third-largest global aviation network.
Up to five new Saf production plants are planned for the UK, with the government investing in their development.
However, the group said it was concerned investors would be lured to the US and the rest of Europe by "significant" tax incentives, and the UK risked missing out.
In response, it urged the government to introduce a mechanism to close the gap in price between Saf and traditional jet fuel.
On Monday, ministers and aviation chiefs will unveil an action plan for decarbonising the aviation industry at Farnborough Airport.
Transport Secretary Mark Harper said: "This government is a determined partner to the aviation industry - helping accelerate new technology and fuels, modernise their operations and work internationally to remove barriers to progress.
"Together, we can set aviation up for success, continue harnessing its huge social and economic benefits, and ensure it remains a core part of the UK's sustainable economic future." (BBC)