A number of Ryanair adverts have been banned after the company made claims it couldn't substantiate about its "low CO2 emissions".
The Advertising Standards Agency (ASA) has ruled that the budget airline, which flies from Cardiff Airport, broke rules on environmental claims and misleading consumers in its press, TV, and radio ads from September 2019.
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.
There is no common definition of what a "major airline" means.
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.
The watchdog said: "We told Ryanair to ensure that when making environmental claims, they held adequate evidence to substantiate them and to ensure the basis of those claims were made clear."
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.
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"Ryanair is delighted with its latest environmental advertising campaign, which communicates a hugely important message for our customers.
"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.
"We were surprised we had to make these small changes, as the message was approved in other markets and we provided all the supporting data they required."
