The Brazil international joined Corinthians for a fee of 15 million euros, but Berlusconi has little doubt that Pato will eventually find his way back to San Siro.
"Pato will return to Milan in one or one-and-a-half years. His injuries distances him a bit from Milan, but I made a deal with him," Berlusconi told Antenna3.
"He has gone to Corinthians, but he will come back here in the not too distant future. That's what he promised when he hugged me one last time before leaving."
The Milan supremo also had his say on the future of Stephan El Shaarawy, and stressed that the young attacker has the potential to follow in the footsteps of club legends such as Franco Baresi and Paolo Maldini.
"We have been lucky to meet a fantastic person and a true champion like Stephan. He already symbolizes Milan and he can emulate people like Baresi and Maldini," he added.
El Shaarawy has been in fine form for the Rossoneri this term, netting 14 goals in 19 Serie A appearances.