The review, which will be coordinated by the Haystack Group, leaves Jamie Oliver's future as a brand spokesman uncertain. Oliver has fronted the supermarket's campaign for the past five years. His contract is due to expire in May.
Despite persistent denials, Campaign discovered details of the review this week. The review is a massive blow for AMV: Sainsbury's is its second-biggest account after BT. However, it will repitch for the business it won from Saatchi & Saatchi in 1985.
The AMV chairman, Cilla Snowball, said: "It's inevitable and not unexpected news in line with Sainsbury's wider business review. Advertising and agencies are part of that process. We will enter the process with confidence and conviction. We know, love and believe in the brand."
Media planning and buying, which is handled by PHD, will not be part of the review.
Helen Buck, Sainsbury's recently appointed director of brand communications, will handle the pitch, which is expected to take three to four months to complete.
Buck said: "Our focus is on communicating Sainsbury's unique brand positioning of great-quality food at fair prices. By reviewing the account, we can ensure that we are getting the best creative output from our agency to communicate this message."
The review comes at a difficult time for the chain, which was the nation's supermarket of choice a decade ago, but has since fallen to number three, behind Tesco and Asda.
Despite ploughing £9m into its seasonal push, Sainsbury's share of spend during Christmas was 37%, three percentage points less than Asda.
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