WPP sees ad slump past worst

French advertising group Publicis said in February it believed the worst of the economic downturn was over and said it aimed to return to sales growth this year and achieve stable margins.

Its forecast for flat margins however disappointed the market.

Publicis reported a fourth-quarter organic sales decline of 5.4 percent while the same metric fell 6.3 percent at Omnicom.

Sorrell told Reuters this week he had seen a "significant" change in trading in November and said the firm had now hit a stabilisation phase.

"Like-for-like revenues were almost the same in January 2010, against January 2009, an encouraging return to stability, a trend first indicated in November 2009," the company said on Friday.

"Although this return to stability seems widespread both geographically and functionally, there is no marked growth as yet, even against weak comparatives."

(Reporting by Kate Holton; Editing by Hans Peters)