Sannino, who is under contract with Siena for a further year, has received an offer to guide the Sicilian outfit next season and hopes his current club will release him.
"I owe a great deal to (Siena president) Massimo Mezzaroma, but I have chosen Palermo," Sannino said to Gazzetta dello Sport.
"I am waiting for a meeting between Mezzaroma and (Palermo president) Maurizio Zamparini to take place and we will see what the future holds for me.
"Without a doubt, Palermo are the real alternative to Siena for me.
"I hope for the sake of everyone that we can break off without any problems.
"I think Mezzaroma will understand, as there are many situations to take into consideration.
"Many important coaches have worked at Palermo and it can be a great chance for me to grow professionally.
"I hope to have this opportunity."
Palermo are looking for a new manager after dismissing coach Bortolo Mutti at the end of the season.
Mutti endured a disappointing spell with Palermo, with the team finishing 16th in Serie A - two places and one point behind Siena.