Lyon president Jean-Michael Aulas has blasted Spurs for trying to go back on their deal to sign Hugo Lloris.
Aulas claims Tottenham chairman Daniel Levy asked to change the details of their original agreement with the French club, despite already signing off on a fee.
"We have had people speaking all night with Daniel Levy. He talks a lot and goes back on what we've agreed in writing," Aulas explained.
"The things as they were at 5am were not the same at 10am. I think we have to make sure we get a certain amount of value because it's important that Hugo can go to a quality club that allows him to do himself justice from a value point of view, so that he can feel right about it."
It is now uncertain whether the two clubs will reignite negotiations, with the deal currently stalled.
"At the moment we're talking about whether he can come back to say his goodbyes to the supporters, to his team-mates, so we can honour him, this truly great player and brilliant man. I would put it at 50-50 that Hugo goes to Tottenham.
"Although from the outset we've submitted to agreements I would now put it at 50-50 that he'll be going there. Agreements have not at all been respected. We've done what we can. Hugo has been troubled by the difficulty in these negotiations."
Lloris would be a massive loss for Lyon, as he has been the club's first-choice goalkeeper for the past four years.
"He's one of the best in Europe in his position. Our transfer window is open until September 4 but for Tottenham the English transfer window closes on August 31. Either it happens tonight or not at all for Hugo Lloris.
"The negotiation with the Tottenham directors has been the hardest I have ever had to undergo in the 25 years I've been a president. We had email exchanges which have been contradicted, so that's made it very complicated. It's difficult. The Tottenham board's theory is to explain that the economic market is very hard and so we have to get used to renegotiating."
The deal with Spurs has been a long drawn process, and it will be a test of both clubs to get the transfer through before the close of the window.
"We've been negotiating all night. The first negotiation was at the start of the window, about a month-and-a-half ago, through an intermediary who was a French lawyer, who lives in Lyon. And then nothing for about a month-and-a-half. The negotiation then picked up again about a week ago."