A meeting was held on 30 May between Paul Eden, the director of Field Brand Innovation at Ogilvy, and David Muir, the Prime Minister's director of political strategy and a former WPP Group employee, to discuss the project.
However, Gary Leih, the chairman and chief executive of Ogilvy Group UK, rejected the business because global Ogilvy policy dictates its agencies do not work with politicians or political parties.
Saatchi & Saatchi handles the Labour Party's advertising, but was not approached with this brief.
It is understood that the task is data-oriented, rather than creative. Number 10 is now thought to be approaching more agencies with the business.
Over the past six months, Brown has recruited advisors from the media and advertising sectors, including Muir, to improve his public image.