Asda and Tesco are squaring up in the latest price war designed to appeal to shoppers being squeezed by the credit crunch and rising prices for food staples, petrol and energy.
Asda is dropping the price of ten top-selling items this weekend to just 50p each.
These include staples such as bread, butter, eggs, and some fruit and vegetables. Bananas, grapes, potatoes and sausages are also featured.
The offer is available in all Asda's 329 stores from Friday to Sunday.
Meanwhile Tesco has declared a series of "inflation-busting" prices with cuts of up to 50% on some 5,000 items.