The boss of Marks & Spencer has told customers the retailer is “working day and night” to manage the cyber attack that has forced it to temporarily shut down its online operations.

Stuart Machin said he was “really sorry” for the disruption to services, but did not say when normal business would resume.

M&S’s problems began over the Easter weekend, with customers reporting problems with Click & Collect and contactless payments.

Last week, the company confirmed it was dealing with a “cyber incident” and paused online orders on its website and apps.