Rooney - who is undergoing treatment for a hamstring injury - is reported to be "angry and confused" after recent comments from manager David Moyes appeared to indicate the 27-year-old would be a back-up option for striker Robin van Persie next season.
The England forward believes he has nothing left to prove after nine successful seasons at Old Trafford, and is disappointed by his manager publicly stating the need to "get him back to where he was".
Rooney has also taken exception to United's stance over his contract, with the club insistent they are prepared to let his current deal - which has two years left to run - expire.
Speaking last week, United chief executive Ed Woodward said of Rooney's position: "No contract renewals are being discussed. I am not sitting down with any player on an extension and there is no trigger date in the diary.
"Would we be afraid to run a contract down? Of course not."
Despite the growing unrest between player and club, Moyes has repeatedly stood firm on the striker's future, saying the 27-year-old is not for sale - although Chelsea manager Jose Mourinho is a confirmed admirer.
Speaking at the start of Chelsea's Far East tour last Friday, Mourinho said of Rooney: "He is a player I like very much but I can say no more than that. Being fast and direct, I like that, but he's a Manchester United player."