The telecom player is looking to appoint one agency group and has invited WPP, the incumbent, and other holding companies to pitch.
The ecommerce player is now a contender as the world's biggest advertiser.
WPP chief executive outlines plan to be 'creative transformation company'.
Hot in 2018: Sorrell saga yet to reach final chapter. Watch an exclusive video here
Media buying, particularly performance marketing, is high on the agenda, Sir Martin Sorrell and Victor Knaap revealed at a Campaign event in London.
Advertising network and customer engagement specialist to join forces.
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