The WPP-owned integrated agency won a place on the roster following a competitive review. It takes a place alongside Mars/Y&R and Savvy Marketing.
The appointment follows G2's decision to rebrand to G2 Joshua. It will revert to using its original name Joshua, which it dropped two years ago.
The agency has started to reintroduce the Joshua name over the past few months. However, from February the agency will officially be known as G2 Joshua under the new proposition, "Connected agency for a connected world".
In 2009, Joshua G2 rebranded as G2 to bring it more in line with the rest of the G2 Worldwide network, part of the Grey Group.
G2 Joshua will also move west from its cramped offices on Wells Street in central London, to WPP-owned building, 1 Knightsbridge, where fellow group agency JWT is based, as part of its expansion plans.
Tim Hipperson, chief executive at G2 Joshua, said: "The reason we decided to bring back Joshua is because it had huge amounts of recall. We're bringing back its creative heritage. This is the third wave of the agency and as part of it, we'll move to Knightsbridge for growth."
G2 and Coca-Cola would not comment on the roster appointment.
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