The advertising watchdog has banned two press ads for Asda’s 10% Price Guarantee following complaints from Tesco.

Tesco had complained that the ads were misleading, after they claimed that “Only one supermarket is… always 10% cheaper”.

The Advertising Standards Authority agreed, suggesting Asda had blurred the line between promoting its price guarantee website and making a claim to be 10% cheaper than its rivals.

In its ruling, that ASA said the ads would be “ambiguous to consumers as to whether Asda offered a ‘lowest price’ claim or a ‘price promise’”.

The watchdog concluded by ordering that the ads must be scrapped. In future ads, Asda must “make clear that it offered a price promise and not to confuse that price promise with a lowest price claim”.

An Asda spokeswoman criticised the ruling, saying Tesco were the only ones confused by the ads.

“The fact that it’s not customers complaining, but a competitor that can’t match our price promise, says it all,” she said. “Our customers love being able to check how much cheaper their shopping is at Asda and they’re not confused in the slightest.”

Tesco welcomed the ban. “This is good news for shoppers, who deserve clear and transparent information about prices,” a spokeswoman said.