"People say look at the money Tottenham have spent, but they spent a lot last year and with all due respect to them, where did it get them?" he told the Birmingham Mail.
"They spent £16.5m on Darren Bent which I think was more than the total amount we spent.
"Darren Bent's a great player and if he's given games, he'll be a good scorer but they rarely played him.
"You see things like that at Tottenham probably because they have got the money.
"But we've got a good squad and we've just got to look after ourselves - we can't afford to worry about what anyone else is doing.
"If someone's got £100m more to spend, we're still not going to have that."