Pogba injured his hamstring in United’s Champions League win over Basel easier this month.
The Red Devils had initially hoped that the Frenchman would only be missing for a few games but concern is growing that he will be out until at least mid-November.
Mourinho says he can not have a ‘positive answer’ about Pogba and has hinted he’ll be missing for a long time yet.
Discussing United’s team news ahead of tomorrow’s clash against Crystal Palace, he explained: "Michael Carrick and Phil Jones are out, they were out and tomorrow some will be out.
"From all the injuries we had I hope we can have some available tomorrow.
"Paul Pogba's injured he cannot play tomorrow and his injury I cannot have hope like Jones or Valencia who I can see in training and hope for positive answer.
"So don’t speak about long term injury – Zlatan Ibrahimovic, Paul Pogba, Marcus Rojo - I don’t speak about them.”
United take on Palace having only just got back from their lengthy trip to Russia for their Champions League tie against CSKA Moscow.
The Red Devils won that Group A match 4-1 and will be confident of seeing off a Palace side who haven’t scored a Premier League goal this season.
But Mourinho admits he is worried about his side’s mounting fixture list
He said: “I look at the period of time we have to recover from match to match. It's the only thing that concerns me and makes me think."
