The 21-year-old was the subject of a long-running internal investigation at Old Trafford following his arrest in January 2022 on suspicion of attempted rape, assault and coercive control.
Those charges were dropped in February 2023, freeing Greenwood to resume his professional career.
He trained away from the rest of United’s squad over the summer, before eventually sealing a loan move to La Liga side Getafe at the end of the transfer window.
The one-cap England international remains under contract in Manchester through to 2025.
Arnold has, however, suggested that his time with United is over.
The Red Devils’ chief executive held an extraordinary all-staff meeting on Monday following reports in The Athletic of “in-house discontent”.
Arnold was quizzed on the subject of Greenwood during those discussions, with certain members of staff – including the club’s women’s team – having expressed their concern at the forward potentially being reintegrated into the first-team ranks.
When answering a series of pre-submitted questions, Arnold said when asked if promises could be made regarding Greenwood’s continued absence from long-term plans: “There’s no expectation of Mason playing for Manchester United.”
Greenwood made his debut for Getafe over the weekend – stepping off the bench to take in 13 minutes of game time during a 3-2 victory over Osasuna.
He was the subject of “die” chants from away fans during that contest, but Getafe have continued to give him their full support.