Manchester City have splashed out £217million in the last couple of months, including the £50million capture of right-back Kyle Walker from Spurs.
Meanwhile, Manchester United have spent £75million on Romelu Lukaku and Chelsea have landed Alvaro Morata for £60million so far this summer.
Some Spurs fans have voiced their frustration with their clubs’ lack of spending, having so far failed to make a signing while their Premier League rivals have all strengthened.
But, Levy insists the club will contonue to be run ‘in a very appropriate way’, which has subsequently been praised by Man United boss Jose Mourinho.
Speaking during Tottenham’s pre-season tour of the United States, Levy said of the spending so far this summer: “My view is that it’s totally unsustainable.
“We’ve managed the club, we think, in a very appropriate way.
“We have a duty to manage the club appropriately. I don’t think that long term for any club it’s sustainable to spend more than you earn. You can have periods where you do, but over the long term you can’t.
“I think some of the activity that’s going on at the moment is just impossible to be sustainable. If somebody is spending £200million more than they’re earning, then eventually it catches up with you. You can’t keep doing it.”
Spurs have invested more than £100million on their training facilities, and are also expecting to fork out a final figure of around £750million for their new stadium.
Levy acknowledged it was a challenge to finance the building of their new 61,000-seat home, which is due to open in 2018, but insisted it had not affected this summer’s transfer dealings.
He added: “We have to find the right balance but I can honestly say it is not impacting us on transfer activity because we are not yet in a place where we have found a player that we want to buy who we cannot afford to buy.”
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