Moore, who is currently the president and chief creative officer of the Seattle office, will now take responsibility for the whole of North America.
The move follows the departure of Dave Droga as the worldwide creative officer at Publicis, a post that the agency has now eliminated.
Moore will remain based in Seattle, but will relinquish all management duties for the office. Randy Browning, the chief executive, will assume that responsibility.
During his career, Moore has worked at Wieden & Kennedy and Fallon on clients including Microsoft, United Airlines, AltaVista and Lee Jeans.