Drivers cashed in on cheap fuel after a technical hitch meant a Tesco site sold fuel at 40p per litre for nearly a week.

The faulty pump went undetected by staff at the Milton branch of the supermarket as customers flocked to the forecourt for the bargain unleaded petrol, with a regular 60-litre tank being filled for just £24. Staff only became suspicious after they had to deal with traffic problems caused by the queues of customers which reportedly snaked around the roundabout to the entrance of the store.

A Tesco spokeswoman chose not to comment on how the slip-up went unnoticed for so long, saying: "This was a technical fault at the pump and an engineer was called to rectify the problem.

"Although we always aim to keep prices down at the pumps unfortunately we could not maintain this price indefinitely."