The Belgium international has been heavily linked with a big-money transfer this summer after three and a half seasons in Rome.
Chelsea have held a long-standing interest in the 29-year-old midfielder, while ambitious Milan are prepared to splash the cash in an effort to restore domestic dominance.
Roma, though, have no intention of parting with their prized assets and have made Nainggolan very much a central character in their promotion campaigns for the 2017-18 season.
Mohamed Salah is another of those to have generated transfer speculation, with Liverpool among those said to be keen on the former Chelsea forward.
Roma are understandably reluctant to see key figures head for the exits after pushing Juventus close in this season’s Serie A title race.
They will be looking to take the crown next season, while also staying competitive in the Champions League.