Pogba has been linked with a move away from the Old Trafford club for some time and has not played for United since Boxing Day due to injury.
According to the Daily Mail, Madrid and Juventus value the Frenchman at around £50m, which is way short of what United are thought to want for the player.
The 26-year-old joined United for £89.3 million in 2016 from Juve but has failed to live up to the expectations of many fans.
Pogba has scored 31 goals in 143 appearances for the club that he started his professional career at in 2011.
After leaving United for the first time in 2012, he joined Juve where he won four Serie A titles. body check tags ::