Somerfield today turns up the heat in the supermarket price war by launching one of the largest ever on-going price promotions, investing £0.5 billion in discounted products in the first 12 months alone. Recently Asda announced it was reducing prices by £52 million over the first 80 days of 2001 and Tesco said it would cut £70 million off a range of products. Megadeals, however, will give shoppers £26 million in savings in the first two weeks.