The Naked start-up will bring digital communications planning operation closer to the creative agency Fallon. The two agencies are expected to bring a wide range of clients to the new venture.
The new agency name is to be announced this week, but it will definitely not operate under the Naked umbrella.
Jon Wilkins, managing partner of Naked, said: "Naked's proposition is to offers customers communications advice from call centres to brand events, and now we're taking the next step forward."
"The digital world is about to kick off again," he added.
Fairhead has risen through the ranks at WPP's digital arm Outrider from a client services director to managing partner in 2002.
Fairhead and Johnson will work out their notices at Outrider, which is part of Mediaedge:cia, and begin their roles at the new agency shortly.
Rob Norman, Mediaedge:cia chairman and chairman of Outrider, said: "They're both really great people and we're sorry to see them go. We're actively recruiting for replacements though."
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