The Serb also stated his belief that the Red Devils may not be favourites for the league, despite holding a six-point lead, while he insists Mario Balotelli can be a "top player"
The 31-year-old has been continually linked with Italian league-leaders Juventus, among others, but speculation about big-money transfer to rich Russian club Anzhi Makhachkala has also been reported.
The Serbia international did not deny the reports and suggested he could be open to a move, with a number of top sides from Italy able to compete in Europe, revealing he was close to moving in the past.
He told Corriere dello Sport: "My future in Italy? Who knows? In the past I was close to Fiorentina and Parma.
"Juventus and Milan have the quality to compete for Champions League."
Vidic has been plagued by injury in recent times and has missed that last two months with knee surgery, with the centre-half also suffering a cruciate ligament problem problem that cut is campaign in half last season.
The Serbia international is due to return to Premier League action against Sunderland on Saturday, with the Red Devils six points ahead of rivals Manchester City.
However, he is not sure whether his side are favourites for the title, despite holding a big advantage after dramatically defeating Roberto Mancini's men at the Etihad Stadium last week.
"I don't know if Manchester United is the favourite club to win Premier League," he continued.
One player who failed to live up to the billing of the Manchester derby was City forward Mario Balotelli. The Italian was replaced before the hour mark after a less-than-inspiring display.
But Vidic thinks the controversial attacker has all the attributes needed to be a world-class player, but hinted that he may need a change of attitude.
"Balotelli may become a top player," he added. "It all depends on him."