Tottenham chairman Daniel Levy believes some of the spending by Premier League clubs is unsustainable as he defended Spurs' lack of transfer activity.
As sides in England's top flight have splashed the cash, Tottenham are yet to bring in any players this close-season.
Several players have been sold or released, including full-back Kyle Walker joining Manchester City for a reported £50million.
Levy feels some of the spending at the moment cannot continue, saying: "We have a duty to manage the club appropriately.
"Some of the activity that is going on at the moment is just impossible for it to be sustainable.
"Somebody spending £200m more than they're earning, eventually it catches up with you. And you can't keep doing it."
While Spurs are yet to spend, they have managed to hold onto their stars, including Harry Kane, Dele Alli, Toby Alderweireld and Eric Dier.
Levy admitted to difficulties due to the club building a new stadium, but insisted there was not yet a player Mauricio Pochettino had found that Spurs could not afford.
"Obviously when you're building a stadium of this magnitude and it all has to be privately financed - there's no state help whatsoever - it is a challenge," he said.
"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."