Zentropy previously managed this business, and will continue to handle digital work for the Unilever Frozen Food and Ice Cream divisions, which include Birds Eye, Walls, Magnum, Solero and Captain Birds Eye.
Initiative already handles traditional media planning and buying for Unilever, an account believed to be worth around £170m in the UK. The move will make Initiative responsible for digital strategy for the brands Persil, Lynx, Marmite, Flora and Pot Noodle.
According to a spokesman for Initiative: "The decision was taken to align and simplify media planning and buying operations within Unilever, therefore giving the online business to Initiative for the companies with which it already works."
Despite losing some of its buying business to Initiative, Zentropy, which was named Revolution magazine's agency of the year for 2002, will remain the preferred agency for digital creative work.
Unilever appointed Zentropy, which is part of the McCann-Erickson Group at Interpublic, to lead the interactive strategy across its entire brand portfolio for the UK in November 2001.
At the time, the appointment reflected a bid by the FMCG giant to develop a consistent approach and explore new opportunities on the internet and interactive television.
It also marked its first attempt to work with a lead agency for new media rather than continue to work on an ad hoc basis.
Zentropy won the account after a pitch against Outrider, Quantum New Media and Initiative.
Meanwhile, Initiative has recruited David Burns as online manager for Unilever. He was previously at Manning Gottlieb Media OMD, where he ran the Alliance & Leicester and AA accounts.
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