Marks & Spencer, the Bank of England and the CBI hit out at the Chancellor's suggestion that stores limit the price of essentials such as eggs, bread and milk.

The price of eggs, bread and milk would be voluntarily capped under the proposals in return for easing packaging policies and delaying rule changes around healthy food.

The boss of M&S has dubbed government proposals to urge supermarkets to cap the prices of foods as “completely preposterous”.