TESCO launched a labelling system showing the carbon footprint of grocery items.

The labels will allow shoppers to compare the goods' green count in the same way that they can already compare prices and calorie content.

The information will initially appear on 20 items across ranges of Tesco own-brand light bulbs, potatoes, orange juice and washing detergent.

The products will carry a footprint logo alongside the carbon footprint figure, an endorsement from the Government-funded Carbon Trust and Tesco's commitment to reduce carbon emissions.