BAMAKO (Reuters) - Mali's interim President Dioncounda Traore declared a state of emergency on Friday as government forces battled to hold back al Qaeda-linked Islamist fighters threatening to push south from their northern strongholds, an official at the presidency said.

"President Traore has just decreed a state of emergency. The information will be transmitted on national television this evening," the official told Reuters, asking not to be named.

(Reporting by Adama Diarra; Writing by Joe Bavier; Editing by Andrew Heavens)