Guardiola was speaking after it was announced that his club's appeal against a two-year European ban for breaching Financial Fair Play rules had been successful.
"So we have money, but the other clubs have money too. We spend in the last decade more than we did in the past, yes, but 20, 25, 30 years ago, Arsene Wenger — the guy who defends perfectly Financial Fair Play… so Arsene, you know that Manchester City was correct with what we have done — spent a lot of money to be there.
"United with Sir Alex Ferguson spent a lot of money to be there. All the clubs, if you want to be on top, all the clubs (spend); if you don't, it's more difficult."