Sainsbury’s boss Simon Roberts has been forced to apologise to customers after the supermarket giant had to cancel thousands of online deliveries due to technical issues.

Sainsbury's vans

An overnight software update was to blame for the delivery cancellations at the weekend

The grocer said that an overnight software update was to blame for the cancellations on Saturday and said the issue had now been resolved. Contactless payments were affected at stores but the system was back up and running on Sunday.

In an email to customers, Roberts said: “I really understand how inconvenient this disruption to your usual service from Sainsbury’s will be this weekend.

“Unfortunately, we will not be able to deliver the vast majority of today’s groceries online orders. For anyone expecting a delivery today, we have not taken payments for online deliveries and so you will not have been charged.”

Unrelated technical issues also forced Tesco to cancel a “small number” of orders over the weekend. The number-one UK supermarket by market share also apologised to affected customers and said most orders had been fulfilled.

Impacted customers received an email if their order was cancelled and were not charged.

A Tesco spokesperson said: “The vast majority of our online orders are being delivered as normal but due to a technical issue earlier today we have had to cancel a small number of orders.

“We are contacting affected customers directly and we’re really sorry for the inconvenience.”