GroupM is not able to rule out redundancies as it begins a six-month process of merging media agencies Maxus and MEC into a new entity.
A spokesman confirmed that, while WPP’s media planning and buying group did not have a specific target in terms of cost savings, it anticipated "significant" savings from property and back office functions.
He said: "By combining MEC and Maxus together, we believe they are going to be a more powerful force on the global stage".
However, today's proposed agency merger has ultimately been brought about by WPP’s acquisition of digital agency Essence in 2015. While Essence has achieved a "very well-received value proposition" as a digital-first agency in the global marketplace, the shift will allow it to do more traditional media planning and buying too.
"We’re going to be able to get Essence into more traditional media and they will come from a diff perspective from current agencies. This is sort of a holistic, strategic app to create flexibility for GroupM to find efficiencies to reinvest in areas that we can create growth," the spokesman added.
GroupM said it was too early to talk about what would happen to regional chief executive roles.
The WPP media group has also confirmed it had informed clients of its plans ahead of today’s public announcement.
"We’ve been speaking to them before this announcement and we will be working out solutions for every client. It’s a collaborative process and it’s going to be a seamless experience because we’re taking our time with it."