The CMA issued two £30,000 fines to Asda for “sending a representative to attend a compulsory CMA interview who was not equipped to provide evidence on certain topics” and “failing to respond completely to a compulsory written request for information”.

The watchdog also found both Asda and Morrisons “each made the decision to target higher margins” on fuel sales in 2022. The report said Asda’s fuel margin in 2023 was more than three times what it was in 2019, while Morrisons doubled its target margin over the same period.