The UK Advertising Standards Authority (ASA) has its hands full with false accusations being thrown around between four of its big retailers.

In the case of supermarket giant Asda vs Morrisons, Asda had its wrist slapped by the ASA for ads that misleadingly claimed its prices were cheaper than those of rival Morrisons. One ad claimed: “Your weekly shop costs less at Asda. Morrisons £76.65. Asda £69.33.” But the comparison was between a 44- and 48-item weekly shop across the two stores. Morrisons also said the products compared might not represent a typical weekly shop.

The ASA upheld most of Morrisons’ complaints and Asda was told to make sure that evidence to back up future price comparison ads was made available on request. Asda, have previously been warned in a similar case, was told that: “Repeated breaches of the Advertising Code could result in further sanctions.”

Tesco has begged the ear of the ASA to ban Ocado's ads claiming it is matching Tesco's prices on 3,500 branded products. The UK’s largest retailer claims grocery home shopping site Ocado is more expensive on at least 500 items and believes the ads are misleading. However, Ocado has insisted it checks its prices against Tesco’s every week. The ASA is still investigating.