The appointment marks a departure for Google, which until now has relied on word of mouth and online marketing, and follows speculation earlier this year that it had begun talks with agencies about its ad strategy.
Although no one from BBH was available to comment, it is understood that Google's European marketing director, Lorraine Twohill, made the appointment. In a statement, the search company said: 'We work with a number of agencies on various aspects of our marketing, and in line with Google's existing policy of working with agencies, Bartle Bogle Hegarty is working on a small project for us.'
Google also works with Sprout on direct marketing and Carat for its media buying in the UK.
The search giant hit the headlines last week with the launch of Google Talk, an internet phone service that could open the UK telephone market to free calls.
Founded in 1998 by university friends Sergey Brin and Larry Page, Google is worth an estimated $10bn (£5.5bn) and employs more than 4000 staff worldwide.
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