The loss of major accounts last year in the US, namely Intel and Volkswagen, hit new business for 2005 hard. It was down by almost €500m year on year to €1.06bn from €1.55bn in 2004.
There was a better showing in Havas's home market of France, as well as the rest of continental Europe and Latin America.
Despite the year-on-year revenue fall, the group, headed by chairman Vincent Bollore, reported fourth-quarter organic growth up by 1.8% and 2.5% for the year.
Fourth-quarter revenues of €420m saw France advance 2.9%, but the UK was down 4.9% where organic growth suffered from what Havas said was a combination of including account losses.
In North America, there was a fall of 5.1% hit by a downturn in the healthcare communications sector.
The news was considerably worse in Asia Pacific in the fourth quarter, where Havas was down 17.2%. The region is still suffering from the loss of its biggest account, Intel, and strong comparisons from the fourth quarter of 2004.
The Havas chairman and main shareholder Bollore is expected to make a move on British media buying group Aegis, in which he has a 25% share, this year.
At the end of last year, Bollore said "the game was open" for a link-up between Havas and Aegis, adding that there was a "certain logic" in merging the firm's media buying operations.
"We have the largest stake in Aegis. We have not invested for nothing, it's a financial stake. The game is open and we are open to reconsidering our position."
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