The Swedish striker initially signed a one-year contract at Old Trafford last summer after joining the Red Devils on a free transfer from Paris Saint-Germain.
The 35-year-old has quashed any suggestions that he could struggle to adapt to the rigours of English football with a string of impressive performances for Manchester United this season.
Indeed, the striker has already scored 20 goals for the Red Devils in all competitions to demonstrate that he still has the ability to cut it at the top level.
And Mourinho is certain that Ibrahimovic will take up the option to extend his stay at Manchester United beyond the summer.
Speaking at his pre-match news conference at Carrington on Friday afternoon, Mourinho said: “I don’t think his contract will be signed, but I’m totally convinced he is going to stay.
“He came with the intention to stay two years but in the minds of everyone the first year is going better than every expectation, he knows we are going to try again to improve next season and try to share with him in a fantastic way probably the last year of his career at the highest level.
“So I’m convinced that he’s staying, he’s adapted to the club, to the situation, I don’t see any problem with his family.
“I gave him the possibility of an extra day off to go to Sweden, he doesn’t want it, so I’m totally convinced he is going to stay.”
Ibrahimovic will be expecting to feature for the Red Devils when Manchester United take on Watford at Old Trafford on Saturday afternoon.
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