Protesters chained themselves to the dairy display

Other members dressed as pantomime cows outside the store at the Cheadle Retail Park on Wilmslow Road, Cheadle, Greater Manchester, on Saturday .

Greenpeace claims Sainsbury's own brand milk comes from cows fed on imported GM animal feed.

But a Sainsbury's spokeswoman said its milk does not contain GM materials.

Cow campaign

Shoppers were confronted by more than a dozen demonstrators dressed as costume cows with a five-metre-high milk bottle carrying the message "GM milk sold here".

Greenpeace campaigner Emma Gibson said: "The reason why GM is still coming into the UK is because supermarkets like Sainsbury's are selling milk from cows fed on GM.

"Shoppers in the North West have been clear on GM, they don't want to buy it and they don't want to see it on supermarket shelves."

But a Sainsbury's spokeswoman countered: "We are disappointed Greenpeace has chosen to target Sainsbury's as this is an issue for the whole food industry."

She said the firm got is supplies from the same farms that supply other supermarkets, schools and hospitals.