The pair, who are were board directors at WCRS, will be based in London and also work on Euro RSCG/Fuel's Reckitt Benckiser account.
Euro RSCG Fuel's London base was set up to help run the $100m global Jaguar account, which was won in March, and French and Rossiter have a strong track record in working for motoring clients.
While at WCRS they worked on the BMW and RAC accounts and prior to that they were group heads at Ogilvy & Mather, where they help set up the Ford Dealership Advertising Association and ran the Ford Escort and Fiesta accounts.
Mark Fiddes, Euro RSCG Fuel Worldwide executive creative director, said: "Mick and Henry understand the difference between an idea that works across borders in any language and an execution written solely for the London creative community. For our international brands, this is a crucial distinction."
French and Rossiter also worked on the National Lottery, Sara Lee and Toshiba accounts while at WCRS.
Commenting on his appointment Rossiter said: "There is a real buzz about the place and the opportunities here are really exciting."
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