The Sainsbury’s grocery website has gone down this morning with a sign up for maintenance telling customers it will be “back shortly”.

The sign tells customers: “We are currently experiencing a very high number of shoppers on our website. To deliver the best possible service we are controlling access to the site at this time.”

It is unclear why the site is down and the sign tells customers to keep checking back as it anticipates “normal service to be resumed shortly”.

A Sainsbury’s spokesman said: “We are aware of technical problems with our website and would like to apologise to customers for the inconvenience this has caused. We are working hard to rectify these.”

Customers have been given a telephone number for urgent enquiries.