However, it excludes work for the 29 regional offices, although Zenith has been asked to provide coordination at the provincial level.
Zenith's win of a chunk of China Mobile's overall budget of Rmb600 million marks the first time the operator has gone from a roster and project system to a consolidated assignment. But China Mobile appears to have had reservations about the switch, including working solely with an international network.
Zenith Asia-Pacific chief executive officer, Antony Young, said: "They had a number of concerns which we had to overcome in the pitch. China Mobile saw local agencies as more responsive and felt that they could better understand its complex approval and management system. It wanted to know if we could work within those constraints and be effective."
Young believed Zenith's work with major international and local advertisers in China - Procter & Gamble, Nokia, pharmaceutical company 999 and white goods manufacturer Midea - helped it secure the assignment.
The account shift signals the increasingly competitive climate state-owned enterprises face now that China has joined the WTO and will need to lift trade barriers. Although China Mobile retains a lot of promise as the market leader - it has more than 100 million subscribers - rival China Unicom is making inroads and escalating the price war. The Government also slashed tariffs last year and issued another two mobile licences instead of the expected one.