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(Corrects organic growth figure in paragraph 2 to 0.9 percentfrom 0.8 percent)
By Gwénaëlle Barzic
PARIS, April 20 (Reuters) - A weak euro helped Publicis to report forecast-beating organic sales growth in thethree months of 2015 and the advertising agency also enjoyed aninitial boost from its recent acquisition of smaller peerSapient.
Organic revenue growth was 0.9 percent on sales of 2.1billion euros ($2.25 billion) in the quarter compared with ayear ago, the company said on Tuesday. That was above analysts'forecasts that revenue would be in a range between 0.5 percentlower or 0.5 percent higher.
The world's third-largest advertising agency, which competeswith Britain's WPP and America's Omnicom, istrying to turn things around after a difficult 2014 in which itsfinancial performance lagged rivals and its planned merger withOmnicom fell apart.
Key to the promised recovery is building on the $3.7 billionacquisition of digital ad specialist Sapient, which wascompleted in February.
"This is an encouraging start to the year," said PublicisChief Executive Maurice Levy, who had previously warnedinvestors that growth would pick up only in the second half.
"The priority this year is clearly organic growth andgetting the machine going again."
Shares in Publicis jumped 4.8 percent on Tuesday at 0740 GMTin heavy trading volumes, making it the biggest gainer on theFrench blue-chip index CAC 40.
Advertising tends to track global growth, sincemultinational companies increase marketing spend when they seebetter demand for their products or services.
Publicis-owned ZenithOptimedia thinks the ad market willgrow around 4.4 percent this year. Publicis has promised tomatch or outperform rival ad agencies.
Europe was a surprising bright spot with sales growing 1.7percent, while the "US, Brazil and Russia were weak," wrote UBSanalyst Tamsin Garrity.
Publicis got a 215 million euro boost from favourablecurrency exchange rates in the first quarter from its exposureto the U.S. and Britain. The beneficial effect from the strongerdollar against the euro is expected to continue especially sinceSapient earns 55 percent of sales in the United States.
Publicis is the first ad agency to report results. WPP isset to report on Thursday, and Interpublic on Friday.Smaller French peer Havas will publish sales on May 5.
David Reynolds, analyst at Jefferies, said the "positivemomentum" seen in the Publicis figures might not be replicatedat other agencies since the French group was in a uniquesituation after its difficulties in recent quarters. ($1 = 0.9313 euros) (Additional reporting by Leila Abboud; Writing by Leila Abboud)
