The move by the department store and grocery retailer follows its introduction of rationing across lines of hand sanitisers and antibacterial products earlier this month.

M&S is the latest food retailer to introduce rationing across grocery lines. Both Aldi and Tesco have similarly put in place rationing of three or four items per person on all product lines, while Asda and Waitrose have also restricted purchases on certain lines, such as toiletries.