The pitch, which is being headed by former EasyJet marketer David Magliano, has shortlisted Delaney Lund Knox Warren, Leo Burnett and WCRS alongside M&C Saatchi.
For the media account, London 2012 has shortlisted PHD, Unity and Manning Gottlieb OMD, as well as Naked.
The winning agency will not only develop the advertising message for London 2012, but will first come up with a brand identity for the London Olympic Games bid, working with Cohn & Wolfe, which has been appointed to promote a logo design competition for the organisation.
London is running against Paris and New York in the competition to host the games in nine years' time.
Last week, London 2012 appointed Mike Lee from European football governing body Uefa to head its PR.
The UK's Olympic bid has already appointed Brunswick and Capital PR to handle media relations.
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