Interest in Dimitar Berbatov's signature is said to be mounting, with his former club Bayer Leverkusen as well as Bundesliga counterparts Bayern Munich reportedly interested.
Berbatov's contract at United expires in the summer, and his future has been the subject of conjecture with the forward having made just four Premier League starts this season.
The Bulgarian is free to hold talks with clubs from abroad, while speculation has suggested his former-club Leverkusen could entertain a deal, having sold him to Tottenham for £10.9 million in 2006.
Bayern and Russian big spenders Anzhi Makhachkala have also been linked with Berbatov, who, according to reports on Sunday, flew to Germany to hold talks over a potential exit.
United, though, are in command of Berbatov's situation as the club could exercise an option in his current terms which would extend his contract by another year, therefore avoiding the risk of losing the striker for nothing in the summer.
Indeed, in December, Red Devils boss Sir Alex Ferguson said: "We'll be exercising (the option to renew]. I think it kicks in in March."
Berbatov, 30, joined United from Tottenham in 2008 for £30 million and has since made 105 league appearances, scoring 48 goals.
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