Banaie, who was hired as vice-president of strategy at Isobar in June, will head the client-facing network, which is expected to incorporate more of a creative element. Internally, the venture is being referred to as "Work in progress - Isobar Global", but it is not expected to carry any Isobar branding once launched.
The move forms part of a significant drive to ramp up digital offerings throughout the media communications arm of Aegis. The group is also set to announce evolved versions of its Carat and Vizeum networks, with the emphasis on better integration between on and offline teams.
Up to 40 jobs are thought to be under review within the group's global client-management team. Changes at the London-based team, which manages clients such as Adidas/Reebok and Johnson& Johnson, are being implemented by Martyn Rattle, who was promoted to the role of chief client officer at Aegis Media last month.
An Aegis spokesman claimed only a "handful" of employees would be affected by little more than "internal tweaking". A consultation period ends next week.
Isobar chief executive Nigel Morris is expected to lead the development of internal digital offerings within the Carat and Vizeum Worldwide teams, while supporting Banaie as he establishes the new agency.
The developments come weeks after the shock departure of Aegis Group chief executive Robert Lerwill. Chairman John Napier has taken responsibility on an interim basis.
Aegis Media faces a crucial period, with several high-profile accounts up for grabs. In November, Carat lost out to OMD in the battle for Renault-Nissan's £650m EMEA account. Carat is again up against OMD for the £58m Vodafone UK account, and is battling Universal McCann to retain banking giant Santander's £32m UK media account.