Balotelli's future is far from certain with many reports claiming that a move to Italy could happen this month.
Inter have been linked with a bid to take him back to the club, but city rivals AC Milan are regarded as favourites while Italian champions Juventus are also believed to have an interest.
"The first refusal right exists," sporting director Piero Ausilio told Italian magazine Panorama. "We will decide whether to exercise it or not at a time when City decides to sell."
It is understood the clause was inserted by Inter when they sold Balotelli to Manchester City in August 2010.