The NFU and ActionAid have joined forces to take out a full-page advert in the national press highlighting the reasons why retailers must sign up to the supermarket ombudsman proposed by the Competition Commission.

The advert will appear in The Times newspaper today (Tuesday May 26) – two days before the deadline for retailers to sign up to the plan – and will carry the message that an ombudsman is in the consumers’ best interests and will not push up the retail price of food.

NFU Deputy President Meurig Raymond said: "Both the Competition Commission and Professor Roger Clarke’s independent research showed an ombudsman would be in the best interests of consumers. A strengthened code of practice proactively policed by an ombudsman will give suppliers great confidence to invest and innovate and lead to a better range of quality products for consumers. There is no reason why retailers should not sign up to its creation."

ActionAid campaigner Jenny Ricks said: "The abuse of market power by retailers affects producers throughout the world, but consumers will be the ultimate losers as the choice of products available to them is reduced. If retailers do not sign up to the ombudsman then Government must step in and deliver it through legislation."

In his independent research Prof Clarke dismissed claims by retailers that the cost of an ombudsman would push up prices for consumers, saying: "The remedies, if effectively enforced, are likely to lead to lower prices in some cases, like agricultural products.

"Even very small price reductions and other benefits are likely to result in consumer benefits that far outweigh the modest cost of an ombudsman. A supermarket watchdog would not only benefit consumers but also be, arguably, in the interests of the supermarkets themselves."

Submissions to the Competition Commission’s in-depth inquiry into the grocery market revealed that a number of retailers employ practices such as retrospective changes to unit prices, rebates from suppliers with without prior agreement, and one-off payments for the opportunity to trade.