LONDON: Tesco, Britain's biggest retailer, on Tuesday followed smaller rivals Sainsbury's and Morrisons, saying it will not let anyone into its stores who is not wearing a face covering, unless they are medically exempt.

To help stem the spread of COVID-19, Tesco said it is also asking customers to shop alone, unless they are a carer or with children.

"To support our colleagues, we will have additional security in stores to help manage this," it added.