The investment bank of JP Morgan fell to a $2.4bn (€1.8bn) fourth quarter loss as writedowns and weak trading drove the unit's revenues into negative territory for the first time in at least four years as Jamie Dimon, chairman and chief executive, said the unit lost several billion dollars more than it would have due to the Bear Stearns acquisition.

Dimon also said in a conference call he still expects Bear Stearns to contribute $1bn in earnings late this year.