France's Publicis promised business would pick up in the second half of this year as the advertising agency recovered from a tough 2014 marred by a failed mega-merger with U.S. peer Omnicom.

It also posted fourth-quarter organic sales growth of 3.2 percent on revenue of 2.15 billion euro, helped by a rebound in emerging markets like Brazil and China, as well as better demand from advertisers across all sectors from cars to consumer goods.