Mourinho: Premier League title not destined for Manchester
Pep Guardiola's side hold an eight-point lead over United ahead of Sunday's derby clash at Old Trafford.
A win for City over their fierce rivals would put them in a commanding position to claim the trophy, while a victory for Mourinho's side looks to be crucial to their hopes of a first league triumph since the retirement of Alex Ferguson.
Mourinho, however, does not believe it is a two-horse race this season, with Chelsea only three points behind United and Liverpool a further three back in fourth.
"We are a better team than last year, no doubts about it. I think City is also a better team than last season," he told a news conference.
"I think we can [win the title] but I think other teams can be champions."
Sunday's clash will be the first between United and City since the terrorist attack on the Manchester Arena in May, when a suicide bomber claimed the lives of 22 people.
Mourinho hopes it will be a "beautiful" occasion that continues the good faith shown by the clubs in the wake of the tragedy.
"I know that a derby is something special for the people," says the boss. "For us, it's about three points but I think that for the people it's a good, positive rivalry." #MUFC pic.twitter.com/qnOmnOYIbt
— Manchester United (@ManUtd) December 8, 2017
"I live a little bit isolated from society, I don't feel it so much," he said. "I really don't have that communication but I don't need that to know a derby is something special for the people.
"For us, it's three points but for the people born in the city and feeling the colours in that good, positive rivalry, it is a special match.
"These are the beautiful things that football can do. We could feel in that period [after the attack] that the clubs were ready to work together for the city. It would be really sad if that was not the case.
"Now this is a football match. An important football match, where I wish everything goes well in relation to the fans. If taken in the right way, the derby's a beautiful thing. Same city, different colours, friends support different colours, even under the same roof some families disagree on the passion of the colours.
"I hope before the game you have a city full of colour, red and blue, and after the game, the same."
Mourinho confirmed Phil Jones and Zlatan Ibrahimovic are fit for the match, with Nemanja Matic to play through an injury, but Eric Bailly and Michael Carrick will miss out and Marouane Fellaini faces a late fitness test.
However, the United boss would not offer any indication of his tactical plan or line-up.
"Football is unpredictable. As a manager, I can try to define a game plan, to work in a direction but football is unpredictable," he said.
"We don't know what can happen, there are so many things that are out of control that can totally transform the direction of the game. I wouldn't risk saying what game we are going to have."