"City have the richest owner in the world but I still see United as the biggest club in the world," insisted the winger.
"United have a status and history that it has taken years to build up. It stretches back to the Busby Babes, to players like Sir Bobby Charlton and George Best. It will be very interesting to see what happens at City, but what we have at United is very special.
"You see it when we go abroad in pre-season, you appreciate how popular United is. We have fans in India, China, South America. That popularity is a result of our history. Money can't necessarily get you that.
"A lot will depend on the players they buy, how quickly they gel and how they handle the attention," he added, in response to being questioned about whether City can break into the top four.
"People have been asking for a long time now if somebody can break into the group. People will expect that club to be City and there will be a lot of pressure on them each season now. Everybody's attention will be on Manchester."