Mainoo had previously asked to join a team on loan in the summer, but his request was rejected by the club.

Since Ruben Amorim took over as manager, Mainoo has found himself falling down the team's pecking order, with the new manager unable to find a place for him in his preferred 3-4-3 formation.

Mainoo's lack of playing time has also led to him being left out of England squads by manager Thomas Tuchel, who believes he needs more experience to be considered for selection.

Mainoo has two years remaining on his Manchester United contract, and his limited playing time is a significant concern for the club.