The grocery war between the big four has been further stoked this week as Tesco lodged another complaint about Asda’s Price Guarantee.

The news comes as the Advertising Standards Authority (ASA) this week upheld four of the nine previous complaints against Asda’s Price Guarantee, made by Tesco and Morrisons. They complained that Asda did not make it clear the price guarantee did not apply to non-grocery items, such as books and football products, that appeared in the ads.

Tesco’s new complaint relates to Asda’s latest tranche of adverts that claim the grocer is 10% cheaper than its rivals. The 10% claim was introduced this year when Asda relaunched its Price Guarantee.

A Tesco spokesman said the 10% pledge “makes the even more misleading assertion that Asda is 10% cheaper than its competitors - which it is not”.

This week’s ruling on the previous complaints means Asda has to be more specific in its adverts and clear in what it covers. Ads in this week’s newspapers still claim to be 10% cheaper but add in the caveat ‘on all your comparable grocery shopping versus Tesco, Morrisons, Sainsbury’s and Waitrose’.

Tesco was pleased its complaints were supported by the ASA, while Asda said it too was pleased that not all the complaints were upheld. An Asda spokeswoman said the price guarantee covered nearly 15,000 comparable products.

➤ City, p11