The European network will launch in Paris in September, with WPP taking a minority stake.
WPP will provide KR Media with support in systems, research and media buying. The network will offer planning and buying across traditional and digital media.
Sir Martin Sorrell, the chief executive of WPP, said: "We are very excited by the prospect of supporting Bruno and Eryck in their new venture and investing in it. We are certain that given their successful careers and reputations, KR Media will be an extremely attractive opportunity for clients and talented people in our industry."
Kemoun and Rebbouh, who have worked together since 1981, left Aegis last November following disagreements with its chief executive, Doug Flynn, over strategy. They are credited with driving the success of Carat International and with building top-level relationships with clients that were envied by rival agencies.
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