The Belgium midfielder, whose family has an Indonesian background, has been linked with the Nerazzurri.
But Thohir insists: "Nainggolan? I haven't talked with him either, or with anyone else for that matter.
"Our project is a long-term one. We want to improve the stability of the club over many years.
"I will talk with Mazzarri and Branca soon, and we will take stock of the situation, discussing possible January signings."
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