The deal will see Yahoo's Go for Mobile pre-loaded on millions of Motorola handsets from the first half of next year.
"Consumers are no longer tethered to just accessing the internet on their desktop computer, so we are bringing the best of Yahoo's services to the device they always have with them and use multiple times every day - their mobile phone," said Marco Boerries, senior vice president for Connected Life at Yahoo.
"Yahoo and Motorola are making it easier than ever before for consumers to seamlessly access their favourite web services, information and content across their PC and mobile phone."
Scott Durchslag, a corporate vice president at Motorola, added: "Our collaboration with Yahoo on exciting future versions of Yahoo Go for Mobile will ensure that our customers and consumers get the most optimised Yahoo experience possible on the coolest mobile devices."
Yahoo and Motorola announced a global agreement to collaborate on projects in July 2005.
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