Trade unions for workers at EDF and Gaz De France went on strike in June in protest at the latter's IPO, which was seen as a dry run for the EDF float.
Euro RSCG's triumph following May's combined advertising and PR pitch could also be a boon for City shop The Maitland Consultancy, which is expected to have a role in the listing of 30 per cent of EDF in October.
The firm has over five million gas and electricity customers in the UK through its EDF Energy subsidiary.
Euro RSCG and its corporate division Euro RSCG C&O beat off challenges from TBWA/Brunswick, DDB/Gavin Anderson and McCann Erickson/Valefi for the brief, believed to be worth at least £500,000.
EDF and Euro RSCG C&O said precise roles and budgets for the campaign leading up to October's £3.4bn listing had not been agreed. Euro RSCG C&O assistant director-general Bernard Sananes is co-ordinating the campaign and handling press enquiries, with Euro RSCG C&O financial comms partner Jean-Yves Leger in charge of investor relations.
Leger said he expected Maitland, in which Havas holds a major stake, to have a role in the deal.
The work complements Euro RSCG's existing role as retained financial comms adviser to EDF.