Paris attacks suspect Salah Abdeslam has told a court he is "a soldier of Islamic State", reports Sky News.
Abdeslam is among 20 men on trial accused of being involved in the 2015 atrocities at the Bataclan music theatre and other venues.
The so-called Islamic State (IS) terrorist attacks, which took place on 13 November 2015, killed 130 people and injured hundreds more.
Nine gunmen and suicide bombers struck within minutes of each other at France's national football stadium, the Bataclan concert hall, and restaurants and cafes in the city.
Police secured the area near the courthouse, on the Ile de la Cite, during the arrival of a convoy believed to be carrying the defendants, and a heavy security presence remains in place.
The alleged lone survivor of the IS group, Abdeslam, is expected to be the key defendant in the trial and is the only one charged with murder.
The same IS network went on to strike Brussels months later, killing another 32 people.
Abdeslam, who abandoned his rental car in northern Paris and allegedly discarded a malfunctioning suicide vest before fleeing home to Brussels, has refused to speak to investigators.
He will be questioned several times throughout the trial, which is expected to last around nine months.
The 31-year-old arrived in court on Wednesday, dressed in black, and was seated behind a reinforced glass partition in the purpose-built courtroom.
Asked what his profession was, Abdeslam told the court: "I gave up my job to become an Islamic State soldier."
"I want to testify that there is no god except Allah and that Mohammad is his servant," he said.
He is thought to hold the answers to key questions about the attacks and the people who planned them, both in Europe and abroad.