The unit will represent Zulu, which was created last year as part of a restructure, as a single entity as well as its individual companies, Claydon Heeley Jones Mason, Agency Republic, sales promotion agency Alcone and software company Code.
Omnicom has appointed Mike Jefferies, business development director at its PR firm Ketchum, to head the unit, where he takes the same role.
Jefferies will spend his time at Zulu looking for new-business opportunities.
Jefferies, who reports to Zulu chief executive officer Martin Brooks, will work alongside Rebeccah Rumph, the unit's marketing manager, and Leo Campbell, deputy chairman.
Jefferies said: "Clients are demanding forward-looking agencies that sell services tailored to their needs and Zulu be being either network or an individual agency does this better than any other current offering."
Before joining Ketchum, Jefferies held new-business roles at WPP's Young & Rubicam and Omnicom's design agency Wolff Olins.
Zulu, which works across 35 countries, has clients including O2, Mercedes and Egg.
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