The restructure, effective immediately and engineered by Lowe's worldwide chief executive Jerry Judge, will see chief creative officer Adrian Holmes promoted to worldwide chairman.
Terry Rosenquist, the network's key figure on its largest client Unilever business, is being promoted to vice-chairman, worldwide.
Sir Frank, who will assume the honorary title of chairman emeritus, said: "My heart will always be in my agency. I take a great amount of pride in what we have accomplished as an agency and confidence in all the next generation of management has yet to achieve."
Sir Frank stepped down from the Interpublic Group board last year along with three other directors as the group announced a new board made up of independent outsiders.
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