The Paris-based owner of MS&L saw revenues fall in its core regions of Europe, North America and Asia Pacific, while revenue in Latin America and the Middle East and Africa rose.
Europe was worst hit, with an organic revenue decline of 6.6 per cent. Most countries were hurt by a slowdown in the first quarter - the United Kingdom dropped 4.9 per cent, France fell 7.4 per cent and southern Europe declined 20.5 per cent.
The Group did not specifically break out PR revenues.
Publicis said that it expects the market's low point will be this summer, with the second half of 2009 proving better than the first. Recovery is expected in the summer of 2010.
Maurice Levy, Chairman and CEO of Publicis Groupe said: 'Our main competitors have published numbers with a decline between 5.6 per cent and 6.6 per cent, clearly showing that Publicis Groupe is gaining market share. The strategy followed over the last few years is bearing fruit: growth in digital activities and emerging markets has helped to cushion the shock.'