Fellaini will be able to leave Old Trafford on a free transfer when his current contract expires in the summer and he is free to negotiate a move with clubs outside the Premier League.
The 30-year-old has attracted interest from clubs in Spain, Italy and Turkey but Mourinho claimed on Monday that he, the club and Fellaini himself all want the player to stay.
“He’s a very important player for me, he’s a great professional who is giving everything he can to help the team,” the United manager said. “There is a desire from myself, the board and the player to stay together, that’s our objective.
“Are we going to reach, going to agree? I don’t know. What I know is myself, the board and the player would like to have a happy end.”
Mourinho has previously sounded more pessimistic about United’s chances of keeping Fellaini, whose camp are understood to have requested a salary of around £125,000-a-week in negotiations.
“I’m happy with his contribution, he is being a great professional for us,” the United manager added. “I know he wants to stay with us, he knows I want him and the club wants him but then there is a paper to sign. You only sign the paper when you are happy with what is in the paper so let’s see what happens.”
Fellaini has made 15 appearances for United during the current campaign after two knee injuries forced him to miss much of the autumn.
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