Lloris' Spurs move in the balance
Aulas claimed negotiations with Levy were the hardest of his 25 years at the top and warned it was "50-50" whether France goalkeeper Lloris joined Spurs before the 11pm transfer deadline.
Tottenham have been linked with a £13million move for Lloris all summer and Aulas admitted they had agreed personal terms with the player.
Speaking after the Europa League draw in Monaco, he said: "We have had people speaking all night with Daniel Levy. He talks a lot and goes back on what we've agreed in writing.
"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.
"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.
"Our transfer window is open until 4 September but for Tottenham the English transfer window closes on 31 August. Either it happens tonight or not at all for Hugo Lloris.
"It's been very, very difficult. I've got 25 years of experience as a president of a club and it's our 16th participation in a European competition in a row. But this is very rare in the football world.
"The negotiation with the Tottenham directors has been the hardest I have ever had to undergo in these 25 years.
"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.
"He has agreed personal terms with Tottenham, he remains under that impression but, since, we have had Hugo Lloris on the telephone for a long time overnight and this morning and he's completely undecided about what happens next.
"The first negotiation was at the start of the window, about a month and a half ago.
"And then nothing for about a month and a half. The negotiation then picked up again about a week ago."