Video: Jose Mourinho says Man City "lack class" (Sky Sports Exclusive)
Concerning Man City's documentary, Mourinho told Sky Sports: "You can have a fantastic movie while respecting others.
"You don't need to be disrespectful to have a fantastic movie. You can be a rich club and buy the best players in the world but you cannot buy class and they showed that clearly, that was really obvious."
Mourinho feels it would be harder to finish better than last season as they finished second.
Jose Mourinho said, "Last season, we put ourselves in a difficult position, because to do better we can only finish first," said Mourinho.
"When I read sometimes and watch sometimes, it looks like we finished sixth or seventh and everybody did better than us. We finished second.
"Liverpool are trying to win the title with their amazing investment. Chelsea have a fantastic squad, Manchester City have a fantastic squad too, Tottenham made an incredible investment by keeping their players, that's the best investment you can make.
"They could be spending £200m but if they lose Harry Kane or Christian Eriksen... the biggest investment was keeping all their best players. Arsenal will be better even though they lost their first match.
"I think it's going to be a very hard season."
Watch the Jose Mourinho's exclusive interview with Sky Sports below: