| Last year, McCann lost more than $400 million in billings, but this year it won Intel's $300 million account.
Chief Operating Officer Murray Dudgeon will fill in for Mr. Kent as CEO on an interim basis, a company statement said.
Mr. Kent had been chairman-CEO since 2002 and has been with the agency since 1996. He held senior regional positions in Europe before ascending to the top spot.
Last year, McCann lost more than $400 million in billings after Nestle consolidated its global media account at Interpublic rival Publicis Groupe. But last week Interpublic scored a major victory when McCann Worldgroup picked up Intel's $300 million ad and media business.
A spokeswoman declined to describe what the specifics of Mr. Kent's new position would be, but the move is believed to have been engineered by McCann Worldgroup's chairman-CEO, John Dooner.
One of the scenarios being considered is to create an entity to oversee Universal McCann and Interpublic's other media network, Initiative. Universal McCann, in particular, has been plagued by major account losses.
Said Mr. Dooner in a release: "Robin will work with me on special Interpublic media projects. Murray will oversee UM's operations and ensure continued media excellence."