Samuel Paty was beheaded on Oct. 16 by an 18-year-old of Chechen origin seeking to avenge his victim's use of caricatures of the Prophet Mohammad in a class on freedom of expression. Police shot the attacker dead.
"This is a battle over security, culture and education," Attal said.
The banned group is named after Sheikh Yassin, a Palestinian Muslim leader and co-founder of the Hamas movement, who was assassinated in 2004. Hamas has denied any links with the French group.