The veteran striker has yet to sign an extension to his deal at Old Trafford amid speculation he could leave at the end of the season, with Napoli said to be interested.
There are reports Ibrahimovic has agreed to stay at United for another year, however, with the 35-year-old having excelled in his first season in English football, scoring 26 goals in all competitions.
However, when asked on Sunday if there has been any progress over talks, Mourinho told a news conference: "I don't have news. For the next two days, I don't want news."
Ibrahimovic was suspended for the 3-1 win over Middlesbrough at the Riverside Stadium, in which Marouane Fellaini, Jesse Lingard and Antonio Valencia sealed three points for a patched-up United side.
Marcus Rashford led the visitors' attack and, despite giving centre-backs Ben Gibson and Bernardo a torrid time with his pace, he passed up two clear opportunities to open the scoring in the first half.
The England international has not hit the back of the net in the Premier League since September 24 but Mourinho insists he is happy with the youngster's performances.
"Marcus is a completely different player to Zlatan," he said. "We have to try to play adapting to his qualities.
"Rashford is in trouble to score a goal; it's really difficult for him. But his movement is top class, his dynamic is second to no-one.
"He's so intelligent, so sharp. The first touch to put the ball in the best position to attack the goal... for me, he played phenomenal.
"Goals will arrive, no problem at all."
Lingard appeared to be limping towards the end of the match but Mourinho hopes the forward will be fit to join up with England next week.
"He had something with his ankle," he said. "It looks minor stuff for me. I hope he can go."