The appointment comes just a week after BBC World and its partner Discovery Communications signed their first distribution deal in the US with Cablevision Systems to air BBC World News.
The channel's launch is set to take place at the end of this month and available to Cablevision's New York customers.
Bill Bruce, BBDO New York chief creative officer, said: "This is an opportunity to change the media landscape and to create brilliant work for a premier news brand."
The agency's work will include strategic and creative campaign development and a poster advertising push in the New York area. Advertising is set to launch from early June.
As well as hiring BBDO, BBC World has also appointed Weber Shandwick to handle PR and Mediaedge:cia to handle media buying and planning.
Seema Kotecha, BBC World's head of marketing, said: "Our research shows that there's an increasing demand from US viewers for an international news agenda and our unique news service will offer them an impartial, global perspective on world events."
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