An ad for Arla organic milk has been banned for using the "misleading" claim that its production is "good for the land".
The Advertising Standards Authority (ASA) upheld a reader's complaint that the ad, which also claimed the milk was "helping support a more sustainable future", was misleading on the grounds that dairy farming was not good for the land.
Arla Foods, which is home to brands including Anchor and Cravendale, said one of the key principles of organic farming was good treatment of the land and that sustainability was at the heart of organic farming.
The impact on the environment was considered in every step of the production process, the firm added.
However, the ASA said consumers would interpret the "good for the land" claim to mean that production of the milk would have an overall positive impact on the environment, taking into account its full life cycle.
The ASA said: "We acknowledged that Arla had provided evidence regarding the organic farming methods used and that they believed this was more sustainable than non-organic farming.
"However, we did not consider they had substantiated that organic milk production had an overall positive impact on the environment, taking into account its full life cycle.
"We therefore concluded that the claim was misleading."
It ruled that the ad must not appear again in its current form, adding: "We told Arla Foods to ensure that in future they did not make environmental claims about their products unless they held sufficient substantiation."
An Arla spokesman said: "The 'good for the land' line reflected that one of the key principles of organic farming is ensuring good treatment of the land.
"According to the Soil Association, organic farming methods offer the best currently available practical model for addressing climate-friendly food production.
"We are disappointed by the decision but we will respect the ruling and have no intention to reuse the specific advert."