Diarra has joined Fulhma on a short-term deal until the end of the season.
The 30-year-old moves to Craven Cottage on a free transfer after leaving Monaco last summer.
The Cottagers are awaiting a visa for Diarra before completing the deal.
Diarra joined Real Madrid from Lyon in a £22million in the summer of 2006, but failed to make the expected impact at the Bernabeu and joined Monaco on a free transfer last year.
