Ozil is out of contract at the end of the season and the 29-year-old has been linked with a move to Premier League rivals United and La Liga giants Barcelona.
Asked about a potential move for playmaker Ozil ahead of Saturday's clash against Arsenal at the Emirates Stadium with Henrikh Mkhitaryan out of favour in Manchester, Mourinho replied: "No comment."
Ozil is not the only Arsenal player entering the final months of his contract, with star team-mate Alexis Sanchez prepared to run down his deal.
United midfielder and Mourinho favourite Marouane Fellaini is also coming off contract at the Theatre of Dreams.
"That's football. They finish their contracts, Fellaini finishes his contract and there are other important players in Europe in other teams who finish their contracts," added the Portuguese tactician, whose second-placed United are eight points adrift of leaders Manchester City.
"Sometimes players decide to go in this direction, which is the right that they have. Players have the right to do that and I don't blame the clubs.
"The clubs, they try. They try, they try, but the players have the right to go into this type of situation and in many times it's good for them.
"Sometimes they can go on a free transfer and they can get huge salaries."
Arsenal sit just four points back on Man United entering Saturday's showdown.