The 22-year-old spent the second half of last season on loan at Cologne and is expected to complete a permanent move away from United after the World Cup.
CSKA Moscow have reportedly made an £8million bid for the winger.
“We made him an offer to stay,” said Cologne director Michael Meier.
“But the sums of money put before him make it hard for any German club to compete.”
Meier added in Express: “But, in the end, there are only winners in the deal.
“We stayed in the league thanks to Tosic, Zoran was able to show his form and is at the World Cup and Manchester United can achieve their asking price.”
