It reported the rise in organic revenue despite a drop of 3.3% in the UK, which Havas blamed on the postponement of government advertising in the run-up to the General Election.
However, it said that account wins, including the $250m (£135m) RadioShack work won by Arnold and the global Diesel account won by ER27, would ensure that the fall would not mean it could not record positive full-year growth. Havas recorded a rise in net new business terms of 45% compared with the first quarter of 2004.
The 1.4% rise in organic revenues compares with 0.7% for the first quarter of 2004. Unadjusted figures show that Havas' revenue for the quarter was down by 7.5% to €330m (£225m), affected by the fall in value of the US dollar.
Alain de Pouzilhac, chairman and CEO, said: "The first quarter has reinforced our confidence in achieving our objectives for 2005. The additional new business gains at the start of the second quarter, including among others the RadioShack account won by Arnold, suggest that our organic growth should be higher in 2005 than it was in 2004.
"Havas' turnaround is substantial, and should be further amplified in the second half of the year."
Havas said that a good performance by Arnold, not counting the RadioShack win, had seen revenues rise by 1.8% in North America. While the UK suffered, France and the rest of Europe saw growth of 2.2% and 2.1% respectively. Latin American revenues rose by 19.7% and in Asia the figure was down by 2.7% because of a poor performance in Australia.
During recent years, Havas has been looking weak as other global advertising groups have consolidated or been bought up. It began a mass reorganisation in 2003, in an attempt to shore up flagging revenues amid speculation that it could be the next target for takeover.
This was heightened when the French corporate raider Vincent Bollore began buying large numbers of shares in Havas in 2004. He now owns 20% of the company, but is yet to make clear what he intends to do know that he owns the stake.
Late last month, Havas said that it had rejected calls by Bollore for four seats on the board of Havas, because he refused to outline his intentions for the company.
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