The Belgian midfielder, who netted a stunner against Wales at Euro 2016, was heavily linked with a move to Stamford Bridge in the summer but he ended up staying put.
And now the 28-year-old has revealed he is happy in the Italian capital and ready to sign a new contract.
“A renewal? I had already decided to stay,” Nainggolan, who has made three club appearances so far this term, said.
“I’m happy here and this thing will work itself out.
“I think we’re both on the same page, we’ll find an agreement soon.”