The left-back's representative claims Louis van Gaal's interest in the Southampton star made the former Netherlands youth international depart for Dinamo Moscow
The out-of-favour left-back, who joined the club on an initial five-year contract from Vitesse two years ago, has revealed he is set to undergo a medical at Dinamo Moscow prior to a proposed transfer.
However the players' agent, Alexander Bursac, believes that while the move will be positive for his client, the 25-year-old has been forced out of the club due to recent circumstances.
"Dinamo Moscow has great plans for the future and they want to challenge for the title," he told Voetbal International. "To stay at Manchester United was not an option for Buttner.
"In the past two years, Louis van Gaal has ignored Buttner time after time. So what kind of perspective does he have when Van Gaal becomes his new club coach?
"Patrice Evra signed a new contract and with Luke Shaw they want to buy another player for Buttner's position."
Buttner's playing position at the club had been put under scrutiny by United's pursuit of another full-back, with Southampton defender Shaw having already agreed personal terms in principle with the club, as revealed by Goal earlier this month.