Sancho's future at United is in doubt after he reacted angrily to Erik ten Hag, who indicated he was not in the squad to face Arsenal on Sunday due to poor training.
United on Monday raised questions about Sancho's condition, but speculation at the club is that he will stay for the time being.
However, sources have now confirmed that the mediators have stepped up discussions on a deal that could send Sancho to the Saudi Pro League. Their transfer window closes on Thursday evening at 10pm.
United are aware of these discussions and are open to deals that could include a loan move or even a permanent transfer.
It is believed that Steven Gerrard's Al Ettifaq is the most likely target. Sancho is understood to be considering his options and is still unhappy about the situation at United in recent days, so a transfer from Old Trafford is under consideration.