The amount of food imported into the UK by air freight rose 31%, or 65,000 tonnes, in 2006, following a sharp rise in imports of ingredients for compound animal feed from the US and Brazil, according to Defra.

Fewer than 1% of food imports in 2006 came by air, though air freight accounted for 15% of carbon emissions from food transport, it added in an update on its 2005 report, The Validity of Food Miles as an Indicator of Sustainable Development.

The figures come a week after the Soil Association outlined plans to introduce a ban on organic produce flown into the UK unless producers meet tougher ethical trading standards.

Defra also said CO2 emissions generated by the UK food industry rose 5% in 2006 to almost 19,000 kilotonnes. HGV food kilometres produced the largest proportion of emissions in the food industry, at 26%, despite distance travelled falling 3% to nine billion kilometres. A 9% increase in shoppers driving to supermarkets raised UK urban food kilometres to 14 billion as shoppers made more frequent trips.

"Transportation is one element in the food chain," said Jeff Rooker, minister for sustainable food and farming and animal health. "The impact on the environment depends on a number of factors. It is important to consider the relationship between the distance travelled by food and the overall impact of how food is

produced."