MORRISONS expects to escape serious criticism in a possible official investigation into “dodgy” special offers in Britain’s supermarkets.

The sector is facing calls for a competition inquiry after consumer group Which? accused firms of ripping off shoppers with misleading and confusing prices.

In its super-complaint to the Competition and Markets Authority, Which? said retailers were creating the illusion of savings through the use of multi-buys, shrinking products and baffling sales offers.

Which? said 40 per cent of groceries are sold on promotion so consumers could be collectively losing out to the tune of hundreds of millions of pounds if only a small proportion of offers are misleading.

It added that it was virtually impossible for people to know if they are getting a fair deal, particularly when prices vary frequently or when consumers are in a rush and may be buying numerous items of relatively low value.

Promotions have become more widely used in the industry over the last 12 months as major supermarkets have cut prices to fight losses in market share to discounters such as Aldi and Lidl.

A spokesman for Bradford-based Morrisons said the firm had been working with Which? for a couple of years on the question of special offers. It is one of the first supermarket chains to introduce unit pricing on price tags, making it easier for shoppers to compare prices and evaluate special offers ‘without needing a mathematics qualification’, according to the spokesman.

He said: “Morrisons has not been ‘called out’ by Which? in its super-complaint to the Competition and Markets Authority which cites various examples of pricing by some retailers. We would not expect to be called out in any future CMA report into pricing, should that come about, due to the work we have done with Which? and the introduction of unit pricing in our stores.”

The CMA must now respond within 90 days to Which?, which said that over the last seven years it has catalogued a range of misleading pricing practices and has passed a report of its findings to the CMA.

Which? executive director Richard Lloyd said: “Despite Which? repeatedly exposing misleading and confusing pricing tactics, and calling for voluntary change by the retailers, these dodgy offers remain on numerous supermarket shelves.

“Shoppers think they’re getting a bargain but in reality it’s impossible for any consumer to know if they’re genuinely getting a fair deal.”