Off contract in June, Casemiro will leave United at the end of this season.
Globo Esporte says Inter is one of the clubs that is following the situation closely.
At the same time, the 34-year-old midfielder has several options to consider. There is interest from both top European clubs and teams in Saudi Arabia and the USA.
Casemiro is now weighing his options for the next step in his career.
A return to Brazil is mentioned as an option, as is a move to a less demanding league in Europe.
However, Inter is highlighted as a serious alternative. The club has a clear strategy to sign established players on free transfers, with president Beppe Marotta driving the transfer policy.
Any move to Serie A will depend on Casemiro accepting a hefty cut on his current €18m salary.