By Sam Webb PUBLISHED: 00:30 EST, 30 October 2013 | UPDATED: 04:01 EST, 30 October 2013 Supermarket Sainsbury's is stepping up its fight against rival Tesco's Price Promise campaign in a long-running row over comparisons between the two firm's products. Britain's third biggest grocery chain is to take its battle into the courtroom by requesting a judicial review against a ruling by the Advertising Standards Authority (ASA) that rejected its complaint over the Tesco pledge. The move comes after Sainsbury's lost an appeal against the ASA decision earlier this month, when a report by the watchdog's independent reviewer Sir Hayden Philips backed the ASA findings.
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Sainsbury's is escalating row with Tesco over price comparison
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It claims Tesco is not making fair claims over prices of certain goods
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Move follows ad watchdog rejecting complaint from Sainsbury's
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