The Nerazzurri's 40-year-old defender is working his way back from a lengthy absence after suffering an Achilles tendon injury late last season.
The Argentine ruptured his Achilles tendon in the 1-0 defeat to Palermo in April, prompting fears that the then-39-year-old would call time on his illustrious 18-year career with the Nerazzurri.
However, Zanetti - who turned 40 in August - subsequently signed a one-year extension at San Siro and hopes to resume training by the end of October.
He told ESPN Radio: "I had a check-up and it was three weeks, and if all goes well I will return to training with the team."
Zanetti, who has made more almost 850 appearances for the Italian giants, joined the club in 1995 and has won a total of 16 honors with Inter, including five Scudetti and a Champions League.