The Northern clubs face off on Sunday at Old Trafford in a top-of-the-table clash.
"Maybe now, City vs. United is a better football match than Milan vs. Inter," Balotelli claimed.
"If I was sat at home and could watch one of the two, I think I'd watch United vs. City.
"Barca vs. Real Madrid is the biggest for the history, but soon United vs. City will be the biggest derby in the world."
Manchester City are currently top of the Premier League table with a two point lead, and a United win would see the reigning champions leapfrogging their local rivals.
"I was at Inter for four years and we were top of the table," Balotelli added.
"Last year in the Premier League we were second. That was the first time in my life I was second.
"For me it's normal to be top of the table - that's where I want to be."
Balotelli is currently enjoying a run of four goals in four games.