Mourinho told reporters: "If we were in another league I would say immediately yes, but in the Premier League the only thing I can say is we can do it.
"In the Premier League it's difficult to say we are going to do it. There is a long way to go and there are very difficult games in front of us, so I don't want to say that.
"What I can say is we are a better team than last season; there is a clear evolution in our team and not just based on the fact we bought fantastic players. But to win the title? There is a long way to go."
Chelsea lead the Premier League by five points over second-place Manchester City.