A LUXURY car manufacturer's environmental claims misled the public, the Advertising Standards Authority has ruled.
The Lexus poster and national newspaper adverts also portrayed speed in a way that might have encouraged motorists to drive irresponsibly, according to the watchdog.
The ruling relates to a campaign for the Lexus RX400h hybrid, which was headlined: "Put your carbon foot down."
It showed an image of the car with its wheels moving against a blurred background.
The Lexus hybrid drive advert included the vehicle's carbon emissions of 192g of CO2 per km in the small print, and claimed it was "better for the environment but without the compromise".
The ASA, which received eight complaints, found that the adverts breached the advertising code.
Surrey-based Lexus (GB) argued that the adverts' focus was not on speed but the fact that hybrid drive technology "generated fewer carbon emissions without compromising performance".
It stated that its green claims for the car were intended to show it was a more environmentally friendly option than its direct SUV competitors, with the RX400h producing lower carbon emissions than other cars in its sector.
Of the complaints relating to speeding, the watchdog said: "We acknowledged speed was not the predominant message of the ads.
"We concluded however that the combination of the headline and the image meant the ads portrayed speed in a way that might encourage motorists to drive irresponsibly and could therefore be seen to condone antisocial behaviour and irresponsible driving."
The ASA acknowledged that the CO2 emissions of the car were lower than those of others in its class but said that consumers would have perceived from the advert that the car had low emissions in comparison with all cars.
"We considered most consumers would understand the play on 'carbon footprint', particularly in the context of an ad for a hybrid car, to suggest the car had low emissions in comparison with all cars," the ASA ruling stated.
"Because this was not the case and the basis of the comparison was not stated, we concluded ad (a) was misleading.
"We noted the body copy stated the RX400h was "better for the environment" but did not state which cars it was better than," it added.
The ASA said the adverts should not appear again in their current form and instructed Lexus not to repeat the claim without stating the basis of comparison.
Mark Roden, general manager, Lexus marketing, Lexus GB, said: "The ASA ruling refers to a Lexus campaign which ended some time ago and therefore no action is required to change or remove it.
"Prior to use this ad was discussed with the Committee of Advertising Practice (CAP), the independent regulator of the UK advertising industry, in accordance with accepted industry procedure.
"We are therefore disappointed that the ASA has subsequently ruled against the campaign as the result of a small number of complaints."
