The striker has been photographed training alone as he seeks a return to professional football.
The Sun quote a source claiming that he is growing tired of waiting around, and has hired a private coach to work with him on his fitness. He has not trained at United's Carrington base.
Greenwood has not played or trained with United since January 2022 but the prospect of him returning to the fold was raised when the the Crown Prosecution Servicedropped charges of attempted rape, assault and controlling and coercive behaviouragainst him in February.
That has opened the door to Greenwood potentially earning a recall under manager Erik ten Hag, but it remains to be seen what decision United will take; they have yet to make a call over his future.
An internal investigation into the England international, who has won one cap, is ongoing and Greenwood is unlikely to wear a United shirt until that is concluded, if at all.
United have reportedly received a number of enquiries into the player's situation.
The Sun reports that there is interest from Italy, with Juventus, AC Milan, and Inter all willing to take him on loan.
It remains to be seen if United would be willing to countenance such a move this summer. United published a list of retained players at the end of the season, with Greenwood included.