The Advertising Standards Authority (ASA) has upheld a complaint by Tesco against a national price comparison advertising campaign by Asda.

The ASA ruled that the ad, which compared the prices of 7,564 products on both Tesco’s and Asda’s web sites, using data collated by on February 18, was misleading.

In the TV and press compaign, Asda claimed that it was cheaper than Tesco on hundreds of items. The ASA said that the claims used online prices rather than those in stores and that the timescale over which the comparative figures were recorded and advertised was misleading.