The decision demonstrates a new determination by the world's biggest brand to come up with ground-breaking advertising after years of lacklustre campaigns.
Last year Coca-Cola spent £15.5m on advertising original Coke in the UK compared with rival Pepsi's £2.3m (MMS).
A spokesman for Coca-Cola GB was quick to point out that there was no formal pitch and that McCann remained its main UK agency. However, insiders spoke of a new resolve to find the best ad solutions for 2003, regardless of their origin.
Mother, Marketing's Agency of the Year for 2002, is understood to be contributing a range of ideas and concepts.
The agency is already on Coca-Cola's agency roster, producing advertising for the Lilt, Dr Pepper and Schweppes brands, but has never before worked on the core Coke brand.
Andy Medd, partner at Mother, declined to comment on the brief. "We're not actually pitching for Coke," he said.
McCann-Erickson, the global agency for the Coca-Cola Company, has held the UK advertising account for Coke for two years and now finds itself fighting to retain its grip on the prestigious brand. UK chief executive Tamara Ingram refused to comment.
Coca-Cola's UK advertising review follows its decision last autumn to use New York hot shop Berlin Cameron/Red Cell as lead agency for its 2003 campaign in the US.
Berlin Cameron, working in conjunction with McCann-Erickson New York, came up with a campaign that focuses on Coca-Cola's 'authenticity' using the strapline 'Real'. This theme is also likely to be used in the UK campaign.
While recent US flavour variants such as Vanilla Coke and Pepsi Blue have given the cola companies a boost in overall sales, their flagship products continue to suffer. Coca-Cola Classic saw sales volume fall 2% and Pepsi's fell by 2.7%.
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