A transformation of food retail regulation is essential in order to preserve competition, according to experts.
Senior industry figures, debating the findings of recent Lancaster University research into retail competition rules, claimed changes in consumer spending behaviour over the past four years have rendered the existing approach - as laid down by the Competition Commission in 2000 - unrepresentative and unfair.
The study, conducted over the past three years, suggested the two-market definition of supermarket and convenience stores outlined by the Competition Commission is incorrect and unfairly discriminatory against smaller retailers.
Former director general at the Office of Fair Trading John Bridgeman called for a public review of food retail legislation to take into account the significant overlap between the two types of shopping.
'The market is changing, and the evidence is that the primary shopping spend is going down while secondary shopping is going up,' he said. 'The smaller stores are competing very effectively with the supermarkets in a way that they weren't in 2000.
'We are probably going to have to wait until the next big acquisition or merger for anything to happen, but I hope the authorities have the courage to reassess earlier assumptions, as this issue is long overdue.'
Big Food Group chief executive Bill Grimsey said: 'This research clearly shows that consumers do not distinguish between the convenience stores and larger superstores. They are using both interchangeably.'