Jon Earl, Vodafone's senior group communications manager, said of the company's involvement with WCRS: "Ultimately this relationship will be phased out."
The move is part of Vodafone's appointment of JWT as its global advertising network, predicted by Campaign in January (Campaign, 25 January), giving it a share of the mobile communications group's £1.5 billion international marketing spend.
Thomas Geitner, the chief executive of global products and services at Vodafone, said: "JWT's appointment will ensure consistency of brand positioning as we introduce new mobile data services."
As Vodafone's global network agency, JWT has the task of providing the strategy and advertising materials for Vodafone's global brand campaigns.
Wieden & Kennedy, appointed in May 2001, remains the global creative agency for Vodafone.
Vodafone is switching 14 of its 16 network operations across the world to the Vodafone brand.
Michael Maedel, the chief executive and president of JWT Europe, the Middle East and Africa, said: "We are thrilled to have won this brand and to partner a global leader in one of the most challenging market sectors in business today."
Robin Wight, the chairman of WCRS, insisted the agency was still in talks with Vodafone over future projects.