There is little in the retailers' submissions to the grocery inquiry to shed new light on claims that supermarkets take advantage of their ­buying power to treat suppliers unfairly.

Most address the matter, including Tesco, which says: "It is simply not in our interest to damage our ­supply chain, as this would be detrimental to our ability to get the best-value products for customers into our shops."

Asda says retailers ­exercising buyer power ­benefit consumers through lower prices.

Retailers back the ­supermarkets' code of practice and Sainsbury's calls for it to cover all retailers.