Less than a third of all spending at supermarkets in April went on promotional products, the lowest level for seven years.

Nielsen, which compiled the figures, said that supermarkets are increasingly looking at year-round lower prices rather than promotional activity in a bid to battle discounters such as Aldi and Lidl.

Meanwhile, in the 12 weeks ending April 23, Aldi and Lidl’s share of the grocery market reached 11.5% – a rise of 13.9% year on year. Nearly half of all households now shop at a discounter every month.

Marks & Spencer, Waitrose and The Co-operative also benefited from sales increases of 3.1%, 2.7% and 1.6%, respectively. 

However, Tesco, Asda, Sainsbury’s and Morrisons all suffered a decline in sales.