Inter sporting director Piero Ausilio said the club remain hopeful of signing Montenegro forward Stevan Jovetic from Manchester City.
The Italian giants have been regularly linked with a move for Jovetic as owner Erick Thohir looks to return the club to UEFA Champions League football.
The signing of defender Nemanja Vidic was a big statement of intent and Ausilio - who spoke about the chances of Inter signing several players - has his fingers crossed that Jovetic joins the former Manchester United captain at San Siro.
"We made contact some time ago with the club, who told us that the boy wasn't for sale," Ausilio told Sky.
"We thought therefore that there was no longer an opportunity. But the window closes on September 2."
Ausilio was also quizzed about the potential of Gary Medel and Roberto Pereyra joining the club.
But while acknowledging a new midfielder would arrive, Ausilio said that coach Walter Mazzarri has a high opinion of the club's options in that area.
"We have agreed with the coach that our midfield is very good," he added.
"Medel has the characteristics that we like, so we are monitoring him as we are others. A midfielder will come in, but we must also think about someone leaving."
Ausilio continued by saying that defender Andrea Ranocchia would remain at the club, claiming: "Inter want to continue the project with Ranocchia and Andrea wants to stay at Inter."
Inter finished fifth in Serie A last term, 42 points adrift of Juventus and 18 behind Napoli, who occupied the final Champions League spot.