Morrisons and Marks & Spencer have previously used unlawful anti-competitive land agreements to prevent rivals opening nearby stores.

The Competition and Markets Authority (CMA) said it has received agreements from the retailers to stop using these illegal tactics, which include restrictions on land being used by a rival supermarket and stopping landlords from allowing competing stores to be opened for periods lasting five years or more.

The Groceries Market Investigation Order was set up in 2010 to ensure shoppers have more choice and access to a range of prices by stopping supermarkets imposing new restrictions that block rivals from opening competing stores.

The watchdog found that Morrisons had breached the law 55 times between 2011 and 2020, while M&S had breached the Order 10 times between 2015 and 2019.

The CMA said that Morrisons, which holds 8.6 per cent of UK supermarket share, had displayed the “poorest compliance record” with the Order it has seen to date.

It added that while 14 of its restrictions have ended, there are still an outstanding 41 restrictions that Morrisons has agreed to address.

Five of M&S’ restrictions have ended and the remaining five it has agreed to address.

"These restrictive agreements by our leading retailers are unlawful," said Adam Land, senior director of remedies business and financial analysis, CMA. "There can be no excuses made for non-compliance with an Order made in 2010, especially when we know the positive impact for shoppers of new stores on the High Street."

The agreements from the retail giants form part of the CMA's targeted programme to enforce the Order's rules on land agreements.

This includes action on similar breaches of the same rules by Tesco in 2020 (23 breaches), Waitrose in 2022 (seven breaches) and Sainsbury’s and Asda in 2023 (18 breaches and 14 breaches respectively).

---