Tesco has been found to have published misleading figures giving the impression that it has met an industry target to halve the use of plastic bags, it was revealed this week.

The Times reported this week that the UK's number-one retailer missed the target and tried to conceal its actual performance.

Seven supermarket chains - Tesco, Asda, Sainsbury’s, The Co-op, Marks & Spencer, Somerfield and Waitrose - signed an agreement last year to cut the number of bags by 50 per cent over the three years to May 2009.

This month they reported, through the Waste and Resources Action Programme (WRAP), that they had not met the target but had collectively achieved a 48 per cent reduction from 870 million bags in May 2006 to 450m in May 2009.

Tesco issued a statement on the same day saying: “Our customers are now using more than 50 per cent fewer carrier bags than they did before.”

However, after being questioned by The Times, Tesco admitted that its figure had been calculated in a different way to the one issued by WRAP. It said that its figure had been adjusted to account for growth in sales and did not reflect the chain’s actual performance.

A Tesco spokeswoman said that it would not be publishing the actual number of bags used and would not be revealing by how much that number had declined.

DEFRA secretary of state Hilary Benn has called on the supermarket giant and other supermarkets to be more honest with customers about how many plastic bags they were issuing. He urged them to publish individual figures so that shoppers could compare them.

The government has threatened to ban free carriers unless supermarkets make progress in cutting the number through voluntary agreements.

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