A luxury brand of shoes and handbags promoted by the actress Sienna Miller was criticised yesterday in a report published by the conservation charity WWF-UK.

The brand - Tod’s - came bottom of the charity’s ranking of 10 luxury groups assessed for their environmental and social performances.

WWF-UK’s Deeper Luxury report warns that Tod’s could be “a liability” to Sienna Miller’s reputation.

The charity did not criticise the actress for endorsing the leather goods brand. But it called on all celebrities not to back firms with poor environmental and social track records.

WWF-UK launched a “star charter” which sets out six factors for famous faces to consider before putting their names to top labels. It wants celebrities to seek expert advice about firms before supporting them.

The Deeper Luxury report gave Tod’s and the Italian jewellery and perfume firm Bulgari the lowest scores of 10 luxury firms, awarding them F grades. The Swiss watch brand Swatch; the French holding company PPR, which owns Gucci, Yves Saint Laurent, Alexander McQueen and other brands; and the Swiss luxury goods firm Richemont, whose stable includes Cartier, Chloé and Mont Blanc, all got D grades.

The jeweller Tiffany was given a D plus. The US leather goods company Coach received a C grade, as did LVMH, whose brands include Moët et Chandon and Louis Vuitton; the accessories firm Hermès and the French beauty firm L’Oréal.

The scores were based on how the firms were judged both by the media and by other NGOs and on analysis of the firms’ own sustainability reports. WWF analysed data on each company held by the Ethical Investment Research Service and Covalence, a Geneva-based company that monitors commentaries and reports about businesses in the European press. Large luxury firms were found to lag behind many other consumer goods manufacturers in social and environmental policies.

Anthony Kleanthous, a senior policy adviser at WWF, made clear there was no criticism of Miss Miller. “We are not saying she shouldn’t be endorsing them but Tod’s may represent a liability to Sienna Miller’s reputation. These stars have a responsibility to make sure that the brands they are endorsing are not damaging the planet. Let’s face it, who wants to pay extra for a dirty brand?”

The actress is abroad and was unavailable for comment. Her contract with Tod’s runs out this month.

Mr Kleanthous said: “Tod’s is bottom because there is just no evidence of any environmental policy or objective. There is no data on its greenhouse gas emissions, water consumption or waste. All these things need attention.” He added: “I accept that luxury brands have low impacts on the environment compared to the oil and air industries but they have greater impact on our cultural awareness.”

Bulgari and PPR both said that they had not seen the report and so could not yet comment.

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