(Bloomberg) -- Air France-KLM, Deutsche Lufthansa AG and Etihad have been told to halt advertisements touting their environmental credentials that a UK watchdog said weren’t backed up by evidence. 

The Advertising Standards Authority said that all three airlines produced paid-for Google ads which gave a misleading impression of the environmental impact of air travel. The ruling was the latest by the ASA, which has previously ruled against green claims made by Lufthansa and Etihad.

The aviation industry is under pressure to decarbonize although the technological challenges for the sector are immense, with hydrogen powered planes decades away. The only way for airlines at the moment to cut emissions is through the use of so-called sustainable aviation fuels, where supplies are scant, and problematic methods such as carbon offsets.

The ASA said that an advertisement by Air France in July 2023 claimed that the airline “is committed to protecting the environment: travel better and sustainably.” The regulator said it expected to see a high level of evidence for such claims and after the airline failed to provide a substantive response, it concluded that the claims gave consumers a misleading impression of the impact that traveling with the airline would have on the environment.

Similarly, Lufthansa touted the ability to “fly more sustainably” in the same month. The airline told the ASA that this was a reference to its “Green Fares” option, which is available to passengers on European flights. Lufthansa said those fares reduce emissions by 20% through the use of SAF and offsets the remaining emissions. The regulator said the airline should have included this information in the advertisement. 

Following the rulings, the airlines can’t display the advertisements again in the form complained about. If the ASA’s edict is ignored, it can ask search engines and social media companies to remove paid-search ads containing the material in breach, and name and shame them including placing its own paid-search ads highlighting the offending ads. 

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