Tottenham has already signed two contracts in this transfer window and has signed Leeds United striker Jack Clarke for around £ 10m before signing Lyon's club record deal of around £ 55m for midfielder Tanguy Ndombele.
Toby Alderweireld and Jan Vertonghen are nearing the end of their careers in North London to find a long-term solution for the center-back.
Should Arsenal fail to complete the change for Saliba, having progressed so far in the talks with Saint-Etienne, this would be seen as embarrassment to the club and a big coup for Tottenham chairman Daniel Levy.
It takes barely 24 hours before Arsenal's preparations were shattered by the refusal of club captain Laurent Koscielny to board the plane prior to the season. Koscielny is determined to return to France this summer and tries to force Arsenal to agree that he can leave the club for free, even though he has one more year on his current contract.
Arsenal simply can not afford to let assets leave the club for free, given their financial constraints, largely due to the bloated wage bill and the inability to qualify for the upcoming Champions League season. They have instituted disciplinary proceedings against Koscielny, who will almost certainly lose the captain.