Despite a a number of contract renewals for key players at Spurs, the north London side are yet to make a signing this window.
"We don't want to lose our best players, but they're aware of course is that everyone has their price".
With Thursday's 5pm transfer deadline looming, Bruce said: "At the moment Spurs haven't got anywhere near what the owners want to consider".
"I don't think we've had a formal bid".
"But the owner has made it pretty clear that he does not want to sell anybody and that includes Jack".
Police detain around 25 gay rights activists in St…
Three policemen were seen carrying one man who looked despondent but still held his multicoloured banner aloft above his head. Police detained campaigners who unfurled rainbow flags or held placards and dragged them into a police bus.
Grealish, who joined Villa as a trainee in 2011, has become a vital part of the team with his energy and drive.
The 22-year-old midfielder has been heavily linked with a move away from Villa since they failed to gain promotion via the playoffs last season. "The best thing the owners have been able to do is not let anybody go on the cheap", he said.
They are thought to want £35million, while Spurs have only offered £20m.
Bruce's troops head into the match as the 6/4 favourites to open the new season with three points, while Hull are priced 21/20 to bag only their second win in 15 matches against Villa.