Atar’s name had already been mentioned in the Belgian press in August as a potential “mastermind” of the Brussels bombings with no further details. Now a “certain consensus” exists that he coordinated the attacks in both capitals remotely from Syria.

Le Monde said that he had lone been based in Raqqa, Isil's de-facto capital in Syria, where a US-backed Kurdish alliance has just launched a campaign to try and retake the city from the jihadists.

Investigators identified Atar as the recruiting sergeant for two Iraqi nationals who blew themselves up outside the Stade de France football stadium outside Paris in November and he is suspected of being the man to whom the Brussels terrorists submitted their plans before blowing themselves up in March.

In June, French police reportedly received a warning that he was seeking to return to France via Albania and was an “armed and dangerous fighter”.

Atar is the cousin of Ibrahim and Khalid El Bakraoui - two brothers who blew themselves up in the March Brussels airport and metro attacks, also linked to the Paris attacks.