Société Générale warned on Wednesday it expects to post only a slight profit for the fourth quarter of 2009, below market expectations, as writedowns and provisions on real estate-linked assets coupled with a slump in investment banking activity weighed on earnings.

The announcement comes amid growing concern that some of Europe's largest investment banks are bracing for a sharp fall in fourth-quarter fixed-income revenue as the credit trading boom that lifted earnings in previous quarters begins to cool.