Villa had turned down a £25million offer from Spurs but a new contract will include a set fee for clubs to meet.
That figure is going to be £60m which is likely to scare off Mauricio Pochettino's team.
In August, Villa boss Steve Bruce said the club was in talks with Grealish but there was one big hurdle preventing a deal.
"We hope to reward him, we're in talks with him now. I hope that it can progress," he said.