CHI's appointment, which is estimated to be worth £10m, is the first to be made by the UK client. The agency pitched against Saatchis and the direct marketing agency Miller Bainbridge to secure the account.
The tactical appointment will see CHI charged with producing non-marque-specific and price-based advertising for the Toyota brand across television, cinema, print and press.
CHI began snatching pan-European Toyota business from Saatchis in early 2005, with a string of appointments made by Toyota's Brussels-based European office.
In February last year, the agency picked up the £8m pan-European launch of the Aygo, a small car aimed at the 18- to 35-year-old market.
CHI's position on the account was strengthened in August last year when Toyota awarded it the £35m advertising brief for the Corolla model across Europe without a pitch. In November 2005, CHI won the £50m pan-European relaunch of the Yaris model.
CHI is now beginning to encroach on Saatchis' UK business and the agency's creative work on the Japanese car manufacturer's Aygo and Yaris marques is running in the UK.
With a global annual spend of £2.5bn, Toyota is the fourth-largest advertiser in the world. It is the Saatchis network's second-largest global account after Procter & Gamble.
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