Tesco has raised the stakes in the retail price war by announcing discounts on 3,000 staple products.

The supermarket will invest £100m this month in a combination of permanent price cuts and promotions. It has also planned a new advertising campaign.

Offers will include three for £3 on Hovis bread and cuts in the prices of Muller Light yoghurts, Weetabix and own-brand tea bags and orange juice.