The midfielder had been managed by his family previously.
“It's so disappointing to have the World Cup in Russia without Italy," Raiola lamented.
“I'm disappointed for my clients [Gianluigi] Donnarumma, Verratti, [Giacomo] Bonaventura, Balotelli... Insigne.
“The blame lies with [CT Giampiero] Ventura, but above all those who put him there. The real shame is that still nothing is changing in Italian football.
"Am I Insigne's agent? At the moment he's resolving things with his current agent. He's a spectacular player.
"Napoli don't want to sell their prized possessions, we'll see what his future will be."