The Red Devils were reportedly looking into bringing the Portuguese ace back to Old Trafford, despite new Real Madrid coach Carlo Ancelotti insisting Ronaldo was not for sale.
But former Blancos coach Mourinho has put a dampener on talk of a potential deal by declaring that the Liga giants are unlikely to allow the 28-year-old to leave since their financial muscle means they will not be pressured into a sale.
"What I know is that Real Madrid is such a rich club that they don't need to sell Cristiano," Mourinho, who shares the same agent - Jorge Mendes - as the former Manchester United star, told reporters.
"And [Madrid] are such a rich club I think they can swallow up any offer another club can make for Ronaldo.I know Ronaldo loves Manchester United and I know he loves the Premier League but I think he is going to stay.
"It's just a feeling. I've had no contact with him, nothing. It's just my feeling."