All continental European Maxus country chief executives will report to de Nardis, who takes up the role with immediate effect.
Maxus UK will continue reporting to Lindsay Pattison, who was appointed to the role of global chief strategy officer of the GroupM agency last month in addition to her existing UK chief executive role, and Pattison will report to the global chief executive.
De Nardis, who splits his time between the agency’s Milan and Turin offices, will retain his current responsibilities in Italy and his role leading the agency’s global Fiat account.
Kelly Clark, global chief executive of Maxus, said: "I'm delighted Federico has accepted this important new position. We’ve built a dynamic and fast-growing agency in Italy under his leadership, and he is liked and respected by our country leaders across Europe."
Dominic Proctor, GroupM president, announced last month that Sakhuja, currently GroupM India and South Asia chief executive, would succeed Clark as global Maxus chief executive.
Clark will become chief executive of GroupM North America. De Nardis will report to Clark until Sakhuja takes up his new duties later this year.
De Nardis said: "Our teams in Milan and Turin have done a fantastic job for our clients and as a result, Maxus has exciting momentum in the Italian market. I'm really looking forward to working with the other EMEA teams to keep that momentum going."