Unilever’s advert for one of its laundry detergents, Persil, has been banned for being misleading about its environmental benefits.

The television advert said Persil was “kinder to our planet”, and featured children picking up litter on a beach.

The Advertising Standards Authority (ASA) said the advert’s claim was unsubstantiated.

Unilever, which owns brands including Hellmann’s and Dove, said it is “disappointed” with the result.

It follows a crackdown by the ASA on “greenwashing” – claims made by firms branding products as eco-friendly, green or sustainable.

In the banned television advert, beaches are shown full of litter and then children are shown picking up the rubbish.

A voiceover said: “For real change we all need to roll up our sleeves and get dirty”.

Text on the screen stating that the product “removes stains at 30C” is shown, with the Persil bottle, which the advert states is made with 50% recycled plastic.

“Tough on stains and kinder to our planet,” the voiceover adds.

A viewer complained to the watchdog that Persil’s claims of being “kinder” to the planet were unsubstantiated.

The regulator upheld the complaint and said that the claims could only be justified if the product provides an environmental benefit over other similar products.

“Although we acknowledged Persil were undertaking actions to reduce the environmental impact of their products, we had not seen evidence or analysis to demonstrate the overall environmental impact of the featured liquid detergents over their full-life cycles, compared with Persil’s own previous products or other products, in support of the claim ‘kinder to our planet’”, the ASA said.

Unilever countered that the advert showed how its liquid detergent was “kinder” to the planet because it saved energy by cleaning in fast washes and at lower temperatures. It also said it was “kinder” because the product used recycled plastic.

A spokesperson for Unilever told the BBC that is was “disappointed” with the ASA’s result.

“We are committed to making on-going improvements to all our products to make them more sustainable and will continue to look at how we can share this with our shoppers”, Unilever said.

The ASA banned the advert because it concluded that the basis of the claim “kinder to our planet” had not been made clear.

The regulator also said the ad featured “various strands of messaging” about Persil’s wider environmental initiatives including encouraging people to “personally take action to care for the environment”, and showing children collecting plastic litter.

“In the context of the entire ad with several messages relating to environmental issues, we considered the meaning and basis of the claim “kinder to our planet” was unclear,” the ASA said.

“Additionally, in the absence of evidence demonstrating that the full-life cycle of the product had a lesser environmental impact compared to a previous formulation, we concluded the ad was likely to mislead,” a spokesperson from the ASA added.