Four Frenchmen kidnapped by Al-Qaeda militants in Niger are flying home this morning after more than three years in captivity.

The French government plane left at 6am carrying the four former hostages. They men reporedly boarded the jet with the French Foreign Minister Laurent Fabius and another minister.

They will be greeted on arrival in Paris by French President Francois Hollande who thanked the President of Niger for obtaining their release.

The exact circumstances of their release have not been released. But the French government said there had been no military assault to free them and no ransom was paid.

The men were kidnapped back in 2010 while working for French nuclear group Areva and a subsidiary of construction group Vinci in northern Niger

Niger began making contact with the kidnappers a few months ago, Nigher's President Mohamadou Issoufou told Le Figaro in an interview.