Panucci later transferred to Inter in 1999, and represented the club during the 1999–2000 season. Panucci was not able to re-capture his previous form during his time with Inter, and frequently clashed with manager Marcello Lippi, later struggling to gain playing time while the team endured a difficult season. Inter finished the season with a fourth-place league finish, also reaching the Coppa Italia final. In August 2000, he was sent on loan to Chelsea, where he scored once in the UEFA Cup against St. Gallen, but only made 8 appearances in the Premier League, failing to find the back of the net. He subsequently moved to French side AS Monaco for the second half of the season, making 9 league appearances and scoring 3 goals. He made 5 league appearances for the club the following season, before returning to Italy to play for Roma in 2001.