The group's performance was fuelled by clients such as ExxonMobil, Pfizer, Reckitt Benckiser and Sanofi-Aventis.
Havas, which owns the Euro RSCG, MPG and Arnold networks, reported a 35 per cent growth in half-year operating income to $105 million.
Vincent Bollore, the Havas chairman, has indicated his desire to merge the Havas media operations with those of Aegis, but recently failed in his fourth attempt to secure boardroom places at Aegis for two of his nominees.