The agency has been handed the business on the back of its work for the Carling and Grolsch brands. The move ends Leith's 13-year partnership with the £1.5m Tennent's account, which is Scotland's best-selling lager.
The Coors Brewers portfolio will now be split between Leith's Edinburgh and London offices. Grolsch, Worthington's and Caffrey's will be run from Scotland, while Carling and Reef will be handled at Leith London.
John Rowley, Leith's chief executive, said: "These are all high-profile names which either lead their sectors or have the potential to, and our brief is to help to drive them to number one."
Leith picked up the Carling account from Bass Brewers in 2000 because of its existing relationship with Tennent's. When Bass was broken up and sold last year, Tennent's and Carling became rivals -- although the conflict was not initially a problem. However, Coors' recent announcement that it is to launch Carling into Scotland puts it in direct competition with Tennent's.
Tennent's greeted Leith's resignation of its business with fury. "This is indicative of our former parent company's obsession to emulate the success of Tennent's," a spokesman said. "Not only has it been actively copying our marketing programme over the past few years, but now it's forcing one of our key partners out of the picture." He continued: "If it is arrogant enough to believe that this kind of action will damage our brand, then it is sorely mistaken."
The news is a blow to Roose, which is currently defending its £10m Velvet toilet tissue account and recently lost its place on the Reckitt Benckiser roster.
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