The advertising watchdog has criticised the Daily Star and Daily Express for running a front page reader offer of £5 off at Tesco, when the deal was in fact a standard offer available to anyone who shopped at one of the supermarket giant's stores.

Richard Desmond's newspapers both ran front page promotions stating a "£5 off shopping at Tesco when you spend £40. Details: Page ...".

On the relevant page there was additional text which said: "Simply spend £40 at Tesco this week and receive a £5 off coupon for your next week's £40 shop …".

Express Newspapers, parent company of the Daily Express and Daily Star, said it did not believe that any part of its front page splash implied that there would be a £5 coupon within the newspaper.

The publisher claimed it was only highlighting that it was possible to get £5 off shopping at Tesco on spending £40.

Furthermore the publisher bizarrely claimed that if it had made it clear that a coupon was not required to get the deal it would have actually encouraged more consumers to buy its newspapers, "because it was an additional benefit compared to coupon offers".

The Advertising Standards Authority disagreed with Express Newspapers' position, saying the overall impression of the promotional ads indicated there was a discount offer only available to readers.

"We understood that promotion was generally available to Tesco customers, rather than only to readers of the Daily Star and Daily Express," said the ASA. "We considered the ads misleadingly implied the newspapers included a £5 discount offer that could be redeemed without further significant conditions when spending £40, for example in the form of a coupon, and therefore concluded that they breached the [advertising] code".

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