Tesco’s website and app is back up after a hack left thousands of customers unable to access their groceries when shopping online at the weekend.

The online issue also left customers unable to make changes to pre-arranged orders or use the search bar.

Over the weekend, customers were told that they may need to enter a virtual waiting room before accessing the company’s site.

A spokesperson for the supermarket chain said: “Our online grocery website and app are now back up and running. Our teams have worked around the clock to restore service, and we’re really sorry to our customers for the inconvenience caused.”

The company said the problem was down to “an attempt to interfere with its systems.” It added that there was no reason to believe customer data was affected.