The decision follows a pitch involving Mars' three global networks -- D'Arcy, Grey and BBDO.
It reflects what industry sources say has been a loss of confidence by Mars in D'Arcy's ability to handle the brand across Europe.
A Mars executive said the company was looking forward to the new work "reigniting" the brand and building its position as a worldwide top seller and the biggest-selling confectionery product in the UK.
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