'City will never be bigger than United,' he said. 'Being successful and one of the most recognised clubs in the world doesn't come from money. It's about history.'
Related ArticlesManchester United face 'Trading Places' momentCity aim to turn back clockFerguson: United can 'handle' CityBlackburn 0 Aston Villa 1Wembley final a must for AllardyceSport on televisionBeckham, who admitted that returning to United with Milan for the clubs' Champions League tie next month would be 'emotionally, very difficult', also insisted he had no plans to quit after this summer's World Cup. Instead, he hopes to play on for another five years.
'I would love to still be playing in five years' time but we will have to wait and see. I definitely think it is possible if I look after myself.
'I haven't said anything about retiring and I'm not thinking about it. I can't even see the logic in the idea. If I was to be picked in the squad and we were to go all the way in the World Cup and win it, people might turn round and say: 'It's a great time to quit.
'But I'd still carry on playing. I wouldn't rule myself out of Brazil 2014. Who knows what will happen?'
Gary Neville, meanwhile, has claimed Sir Alex Ferguson was right to allow Carlos Tévez to leave United for City.
Tévez, who has scored 11 goals in his past 10 appearances for City, is expected to overcome a hamstring strain in order to face his former club.
The Argentinian forward left Old Trafford in acrimonious circumstances last summer, with Ferguson claiming he was not worth the £25.5 million fee being demanded by his economic rights holders.
'I can't disagree with his [Ferguson's] decision on Tévez,' Neville said. 'He was a good player for us, but if the financial demands are too big, then that's just the way it goes.'
United will be without Rio Ferdinand at Eastlands, but the England defender could return to face Hull on Saturday. Dimitar Berbatov is a doubt with a dead leg.
City manager Roberto Mancini also has injury problems, with Patrick Vieira and Roque Santa Cruz both ruled out for a game he admitted is crucial to the club's ambitions.
Mancini said: 'United have been a top club for many years, but we became a big team six months or a year ago. It's not important if they have economic problems and that City have money. We just want to win the Carling Cup because I know how important it is to win the first trophy.'