Pogba was strongly linked with Barcelona during the summer transfer window, with the Catalan giants believed to be desperate to bring the 25-year-old to Camp Nou.
The 2018 World Cup winner ultimately stayed at Old Trafford, however, and has scored twice in four Premier League appearances at the start of the 2018-19 campaign.
The France international's long-term future with the 20-time English champions is far from secure though, and he recently addressed the Barcelona rumours with talk of a possible departure.
The Spanish champions are said to have held talks with Pogba during the summer, but Mourinho has insisted that the midfielder has not expressed a desire to leave.
"Paul came back after the World Cup the week before we started the Premier League," Mourinho told reporters. "We are together two months or so. He never told me he wants to leave. Never. He never told me he wants to leave.
"I can only comment on what is real for me, not in what I read, not on what I listen. I have no direct relation with the people that write or the people that listen.
"I have a direct relation with the players - not [just] Paul - the players. And he never told me he wants to leave. If he doesn't tell me he wants to leave, it's because he wants to stay. That's my conclusion, no?
"If I watch Mr Raiola (Mino Raiola, Pogba's agent) on the screen saying the players wants to leave, and that he is organising a way for him to try to leave or so on, then I will believe. At this moment, I am in the dark. The only thing that is clear for me is that the player never - never in all these days we are together - he never told me that he wants to leave."
Pogba, who has also been linked with a return to Juventus, is expected to be in the United XI for Saturday's Premier League clash with Watford.