The Swede's contract at Old Trafford expires at the end of the season and, with the knee ligament damage sustained in last week's Europa League win over Anderlecht likely to sideline him until well into next season, the 35-year-old's future has been thrown into doubt.
However, Mourinho, who suffered another injury blow ahead of Thursday's Manchester derby with the news midfielder Paul Pogba is out with a muscle injury, refused to discuss what comes next for the striker.
"Now he has important surgery, so I think it is a waste of time to speak about what comes next," said the United manager.
"I don't know, I don't want to know, I'm not interested in it, I don't care about it. I just want the difficult surgery to go well.
"The future is a big surgery, long period of recovery.
"But the future is also in the hands of a very strong guy, mentally very strong who wrote immediately in his social media he will stop when he wants, not when people think, so it looks to me that he is not going to give up, he is going to fight and I am really pleased with that. That is the Zlatan I know.
"I told him, 'You've fought all your life', so I don't see a reason not to fight.
"We think he is in fabulous hands and he has to recover from the injury and prepare himself mentally for the next step.
Read the full article on eurosport.co.uk: I'm not interested in talking about Ibrahimovic future, says Mourinho