Sainsbury’s has asked its customers to shop alone and to wear face masks in renewed efforts to make their stores safer.

That means residents shopping at the supermarket’s Hatch Warren or town centre stores must now go alone and wear a mask, unless they have a medical exemption. 

In a letter to customers this morning, the chain’s chief executive Simon Roberts wrote: “I have spent a lot of time in our stores over the past few days and I need to ask for your help with two key issues to keep you and all my colleagues safe.

"When shopping in our stores, you must wear a mask or visor unless you have a medical exemption. And you should also shop on your own. Thank you for your support.

"Security guards will support our colleagues at the front of store and will challenge customers who are not wearing masks or who are shopping in groups. I know you’ll understand and support what we are trying to do.

"We have also significantly reduced the number of customers allowed in our stores at any one time to ensure social distancing is maintained at all times.

"Together, these steps will go a long way to keep everyone safe, whether you are shopping or working with us.

"Please wear a mask or visor and please shop alone in our stores. Thank you for helping us to keep everyone safe."

More security guards will be deployed to help the store, the chief executive said.

It comes as there are reportedly 400 incidents of abuse towards retail staff a day, according to the British Retail Consortium.