Some UK supermarket pricing practices could be in breach of consumer law, for misleading or confusing consumers through pricing and promotional practices, the Competition and Markets Authority (CMA) found.

The CMA is now taking action to protect shoppers from misleading offers after a thorough examination of supermarket promotions.

The investigation was in response to a Which? super-complaint, which raised concerns about confusing and misleading promotions and a lack of easily comparable prices because of the limitations of unit pricing.

The CMA has since announced a series of measures to improve compliance, bring greater clarity to shoppers and simplify the regulations.

Where there is evidence of breaches of consumer law by any supermarket this could lead to enforcement action, it says.

However, the CMA concluded that these problems are not occurring in large numbers across the whole sector and that generally retailers are taking compliance seriously to avoid such problems occurring.

The CMA also found that more could be done to reduce the complexity in unit pricing to make it a more useful comparison tool for consumers.

To follow up on the investigation the CMA will work with businesses to cut out promotional practices which could mislead consumers.

This includes the practice of running 'was/now' promotions in a supermarket where the discount price is advertised as a promotion for longer than the higher price applied, its says.

Nisha Arora, CMA Senior Director, Consumer, said that they welcomed the super-complaint, which presented them with information that demanded closer inspection.

"We have gathered and examined a great deal of further evidence over the past three months and are now announcing what further action we are taking and recommending others to take.

"We have found that, whilst supermarkets want to comply with the law and shoppers enjoy a wide range of choices, with an estimated 40% of grocery spending being on items on promotion, there are still areas of poor practice that could confuse or mislead shoppers.

"So we are recommending further action to improve compliance and ensure that shoppers have clear, accurate information," she said.