WHSmith has said that an IT error caused its till systems to print receipts with ‘The Queen’s Knickers - £5.99’ regardless of the item being purchased.

The retailer said that the glitch occurred after a change was made to the promotion of a new children’s book in its IT system.

Customers were issued with the incorrect receipts at WHSmith shops last Thursday morning (3 May). The fault was resolved within hours.

The company said in a statement: “We experienced an issue with our tilling system last Thursday, which was resolved very quickly, impacting only a small number of customer transactions.

“Our tills had not been hacked. There was a temporary set-up error in the system due to a promotion change regarding a children’s book, entitled The Queen’s Knickers.”