French investigators have identified a Syria-based terrorist of dual Belgian and Moroccan nationality who is thought to have plotted the attacks in Paris and Brussels, sources close to the case told AFP on Tuesday.

Oussama Atar, a 32-year-old believed to be a member of the Daesh terrorist group, was already a suspect in the March 22 attacks on Brussels but has now been linked to the November 13 atrocities in Paris last year.

"He's the only coordinator from Syria to have been identified during the investigations," one of the sources told AFP.

French investigators have long suspected that the Paris attacks, in which teams of terrorists killed 130 people, were coordinated by one or several people from Syria, but have never named anyone before.

Atar, believed to go by the pseudonym Abou Ahmad, is a cousin of the El Bakraoui brothers who blew themselves up in the Brussels airport and metro attacks.

Another two cousins, Moustapha and Jawad Benhattal, were arrested on June 18 on suspicion of planning an attack in Belgium during a public screening of a Euro 2016 football match, Belgian media reported at the time.

France is gearing up to mark this weekend the anniversary of the Paris attacks.

The Bataclan concert hall, where 90 people died during a show attacked by three gunmen, is set to reopen on Saturday with a gig by Sting.

French President Francois Hollande will lead low-key commemorations on Sunday in the presence of survivors and family members of the dead.