Djamel Beghal is believed to be linked to Bin Laden
Djamel Beghal is believed to be linked to plans to launch a terrorist attack on American interests in France.
Seven people have already been arrested in France and two in Belgium in connection with the alleged plot.
Another French-Algerian man, Kamel Daoudi, was extradited from the United Kingdom to France on Saturday for questioning over the plans.
French network exposed
Mr Beghal was arrested in July in the UAE capital, Dubai, after returning from a visit to Afghanistan.
He is reported to have confessed that a European network was planning terrorist attacks on US interests in France, including the embassy in Paris.
He is now expected to be put under formal investigation on suspicion of being part of "groups linked to terrorist activity", judicial sources said.
Information provided by Mr Beghal is believed to have led to the other European arrests.
Mr Beghal is reported to have links with Osama Bin Laden's al-Qaeda organisation which the US has blamed for the aircraft attacks on New York and Washington.
Le Monde newspaper said he was probably in direct contact with Abu Zubayday who is said to be responsible for recruiting to al-Qaeda.
French authorities began investigating the plot on 10 September - just a day before the US attacks took place.
The French Interior Minister Daniel Vaillant has, however, ruled out any link between the French and US plots.
Europe-wide investigations
Across Europe around 20 people have so far been arrested in connection with the 11 September attacks.
Spanish police say they have broken up a terrorist cell with the arrest of six Algerians who are currently being investigated over possible links to the hijackers.
German prosecutors are also investigating a Hamburg-based terrorist group which they believe was central to the planning of the attacks.
And British prosecutors believe they have established a direct link between a suspect and the hijackers.
They are questioning an Algerian pilot, Lofti Raissi, who is suspected of training four of the hijackers.