Sir Alex Ferguson claims Manchester City will keep on spending until they have won something and admits Roberto Mancini's side are genuine title contenders.
Ferguson's Manchester United side, the only unbeaten team in the top flight this season, face City at Eastlands on Wednesday with a three-point lead over their rivals.
The United manager said the fact both clubs are now challenging for the title will add extra spice to the contest.
Ferguson told Inside United: "It does put an edge on [the game]. I don't believe there's any question about that.
"We know the kind of money they're spending - they've bought another five or six players in the summer and they'll keep doing that until they win something.
"You know that's going to be the way it is and you have to deal with it as it comes along.
"They're up there [challenging for the title], and you can't wait until tomorrow when there's something there today. I'm sure they're thinking that way themselves."
