Cars, lorries and planes are emitting a record 18 million tons of carbon dioxide a year transporting food around Britain, new figures from the Government showed yesterday.

A jump of 6 per cent was recorded in the number of "food miles" by road and air in 2004, according to figures from the Department for Environment, Food and Rural Affairs (Defra).

The figures will heighten concern about the damage done by the supermarkets' policy of flying in products like sweetcorn from Thailand, prawns from Ecuador, or apples from New Zealand. They are also a blow to the Government's commitment - made in its Food Industry Sustainability Strategy earlier this year - to cut the social and environmental costs of food miles on 1990 levels by 20 per cent by 2012.

Environmental campaigners said the figures showed ministers should be doing more to curb emissions of carbon dioxide (Co2), which causes climate change, which has been blamed for this summer's extreme heat.

Food miles are clocked up by air freighting produce often thousands of miles to the UK, trundling lorries round the motorway network and by customers travelling to and from shops.

Amid the rise of the supermarket chains and the all-year round stocking of fruit and vegetable varieties, Co2 emissions from food miles have soared in the past decade. They rose by 15 per cent from 1992 to 2002 and by a 4 per cent between 2002 and 2004, according to Defra.