Ghazi's departure is a blow to the telecoms giant because it announced this month that it was moving its media planning work in-house and out of its incumbent agency PHD.
Steve Huddleston, BT's head of media, is understood to be recruiting anything up to 10 extra media planners to direct its £59m media spend because of the change of policy.
Ghazi has taken the role of media development director at the Leeds agency, returning to the agency side after more than two years with BT.
WWAV is unusual in creative direct agencies in that it has an in-house media division at its London office. It is one of the largest direct media operations in the UK, serving clients including Oxfam, Chelsea Building Society and Which?.
The WWAV creative agency group consists of the main London agency and regional agencies in Leeds, Bristol and Edinburgh.
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