Supermarkets need to source more food from local suppliers or risk losing their customers, according to a survey for Farmers Weekly.

The survey, carried out by NOP, found that 59% of consumers would consider shopping elsewhere in their area if their usual supermarket was not committed to sourcing local produce.

85% of the 1000 people questioned said they wanted their usual supermarkets to do more about sourcing from local suppliers.

The findings add impetus to the ongoing Farmers Weekly Local Food is Miles Better campaign which continues to gather political support.

Conservative Party leader David Cameron will today publicly back the campaign, when he helps to hand over a petition calling on the major supermarkets to stock and label more locally-produced at the Royal Show.

DEFRA secretary David Miliband has also lent his support to the campaign by presenting the prizes to the winners of the Low food Miles Lunchbox Competition.