The Croatia international signed a one-year deal with the Cottagers last summer and went on to make 24 appearances for Martin Jol's side, having netted twice on his debut.
Petric's career began in Switzerland having grown up there, and the 32-year old says that a move back could be on the cards.
"It is true; I have some offers from Swiss clubs. My main goal at this moment in time is to find a club where I will be able to play regularly," he revealed to Swiss newspaper Blick.
Petric spent five years in Switzerland with Grasshoppers and he has been linked with a move back to Zurich, but director of sport Dragan Rapic was unsure if they would be able to meet his demands.
"We didn't talk much about Mladen but we know he is free to leave Fulham so he is an interesting player.
"But I don't know if we are able to offer him a contract that would be good enough for him," he admitted.