Manchester United’s derby rivals raised eyebrows earlier this week after the Citizens made England international Walker the world’s most-expensive defender.
Indeed, Pep Guardiola sanctioned the signing of the former Sheffield United defender in a reported £50m deal from their Premier League title rivals Tottenham Hotspur.
Manchester United have spent £30.7m on Sweden defender Victor Lindelof from Portuguese champions Benfica as Mourinho bolstered his defensive options ahead of the new season.
The 20-time English champions managed to pull off a transfer coup earlier this month when Manchester United completed a £75m deal to sign Romelu Lukaku ahead of Premier League champions Chelsea.
Asked about Manchester City’s incredible deal to recruit Walker from Spurs, Mourinho admitted that he wasn’t surprised to see the Red Devils cough up such a big transfer fee.
“It doesn’t surprise me really,” Mourinho told the club’s website.
“I keep saying there is a big economic power in every club that allows the clubs to say no, or to say you pay what I want or you don’t get it.
“I can imagine Manchester City would like to pay £25m for Kyle, I can imagine that, but I am sure they knocked on Spurs’ door and they were told this is the price. If you don’t it then you don’t get it.”
Mourinho added: “Then you have the option to pay or the option to say no. The market will always be what people ask and what people pay. The strange thing is now I am used to seeing teams paying big amounts for big players.
“Now, everybody is paying big amounts for good players. There is a difference between good players and big players. Now the figures are also really crazy for normal players.”
Manchester United finished in sixth place in the Premier League table last season but still managed to qualify for the Champions League after a 2-0 win against Eredivisie side Ajax.
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