The introduction of a suppliers’ ombudsman would add just 1.25p to the average shopper’s weekly grocery bill, claims consultant Grant Thornton.

Retailers have opposed the Competition Commission’s recommendation to appoint an ombudsman to oversee relations between supermarkets and their suppliers on the grounds of extra cost to consumers. In its interim results last week, Sainsbury's called the post “unnecessary”, while Tesco and Asda have also publicly criticised the scheme.

“Two reviews by the Competition Commission have found sufficient evidence of abuse to warrant the recommendation of an ombudsman’s appointment, but the supermarkets refuse to accept they have lost the argument,” said Duncan Swift, head of food and agribusiness at Grant Thornton. “They are systematically delaying its implementation and are hoping to bury it by casting it as an unacceptable cost to the consumer, while conveniently ignoring the cost to the consumer as taxpayer caused by failing food supplier businesses and lost jobs.”

An Asda spokeswoman said: “Having seen the detail of the proposals, we oppose the introduction of an ombudsman as we believe it would substantially increase the risk of price rises and consumers would suffer. We believe the OFT is much better placed to monitor and enforce the Grocery Supply Code of Practice. There is no need to set up a parallel body.”