"Misleading" Ryanair adverts have been banned after the firm claimed it is "Europe's low CO2 emissions airline".
The Advertising Standards Agency (ASA) has ruled that the budget airline broke rules on environmental claims and misleading consumers in its press, TV, and radio ads from September 2019, and they must be changed.
Both the TV and radio spot referenced "low CO2 emissions" while the text advert claimed "Ryanair has the lowest carbon emissions of any major airline".
After complaints were made, the airline claimed that the phrase "low CO2 emissions" in the radio and TV ads meant "less than average", and in the print promotion, the company compared its CO2 emissions per passenger, per kilometre, to four other big European carriers.
However, the ASA said the "ads [...] must not appear again in their current forms", as the claims could not be substantiated.
They said that customers would interpret the ads' claims to mean that travelling with Ryanair would mean they were contributing less CO2 than travelling with other airlines, which could not be proved.
Transport and Environment, which campaigns for cleaner travel in Europe, accused the airline of "greenwashing" in its campaign.
They said: "This ruling is a reminder that the aviation sector's climate impact is soaring because of a decades-long tax holiday and almost zero regulation of their pollution.
"European governments must, without delay, agree bilaterally to tax jet fuel until EU Vice-President Timmermans secures the end of tax exemption."
Ryanair said it was "disappointed and surprised" by the ruling, and maintained that it is the "greenest" airline in Europe.
In a statement, the company said: "Ryanair's CO2 emissions per passenger km is 66g, which is 25% lower than the other major European airlines.
"The single most important thing any consumer can do to halve their carbon footprint is switch to Ryanair.
"We successfully ran this advertising message in 10 countries across Europe.
"We made minor adjustments to the advertising in the UK market at the request of the relevant approval bodies."
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