The former Islamist mentor of Cherif Kouachi, one of the terrorist gunmen who killed 12 people at France's Charlie Hebdo magazine, distanced himself by describing the attack as "the worst crime a Muslim could commit."
Farid Benyettou, a 33-year-old who says he has left behind his radical past, also revealed that when he had seen Kouachi two months ago "the only thing he wanted to talk about was fighting."
The two had known each other for years and moved in jihadist circles. In 2008 they were convicted together in a French court for their involvement in a network that helped terrorists travel to Iraq to fight US forces.
Benyettou, 33, was sentenced to six years in prison but has trained as a nurse since being released.
He was on a work placement at one of Paris' main hospitals on January 7 when he learned that Kouachi and his older brother, Said, had burst into the offices of the satirical magazine that had printed cartoons lampooning Mohammed, in a shooting attack that left 12 people dead.
"I condemn what was done," Benyettou said in an interview Monday with the iTELE news channel.
"I want to send this message: Islam condemns everything that has been done - the cowardly and monstrous murder of journalists, of police officers and members of the Jewish community. That should not be attributed to Islam. It's the worst crime that a Muslim could commit," he said.
The statement comes after British Culture Secretary Sajid Javid, who is himself of Muslim heritage, said "the lazy answer would be to say that this has got nothing whatsoever to do with Islam or Muslims and that should be the end of that. That would be lazy and wrong. You can't get away from the fact that these people are using Islam."
Benyettou said that in the wake of the attack, he voluntarily went to the intelligence services where he was questioned for two hours before being freed.j
He said that two months ago, Kouachi came to see him "out of the blue."
"The only thing he wanted to talk about was fighting. He didn't want to know about good relations with his neighbors, or acting like a good Muslim," Benyettou said.
He said Kouachi had also wanted to discuss attacks by terrorist Mohammed Merah in the southwestern French city of Toulouse in 2012 which left seven dead, including a rabbi and three Jewish children as he attacked the Ohr HaTorah school.
"I told him I was against (those attacks)," said Benyettou.
Benyettou dismissed suggestions that he had ever been tempted to use violence and rejected the idea that France "oppressed" Muslims.
"I am the proof that it's the opposite," he said. "I have a criminal record that is rather hard for people to swallow. I have been convicted for
terrorism, which is the worst offense. But even so, I have never been discriminated against."
AFP contributed to this report.