Diffiniti will work with its own clients in the UK, which include AOL, HBOS, Teletext, Coca-Cola and Autotrader. It will also work closely with Aegis-owned media network Vizeum.
However, clients from Aegis's other network, Carat, will now be looked after by Carat Digital, which launched in June. The combined online billings of Diffiniti and Carat Digital are in excess of £34m and grew by more than 100% last year.
The new division is to be headed by Robert Horler, the former managing director of Carat Interactive. Horler also heads Isobar UK, Aegis's new global digital network. He will report to Nigel Sharrocks, the chief executive of Aegis Media UK and Ireland.
Sharrocks said: "The online and digital market is developing all the time and we are seeing an increasing demand for a broader range of digital marketing services from clients.
"The growth in digital media is behind the creation of Isobar and the subsequent launch of Diffiniti. Both are part of the first stage of an ongoing programme of development and expansion of our online and digital marketing capabilities."
Isobar launched last month to integrate all Aegis's digital businesses. The Isobar brand is designed to provide a clearer, more integrated model for clients. It incorporates digital services from 25 offices in 19 countries.
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