The player's agent Olivier Jouanneaux has now begun legal moves on his behalf, after legal advice was taken from their lawyer Jean-Louis Dupont - the man who represented Jean-Marc Bosman in the case which reshaped the games transfer system.
Mexes signed a new contract in December to extend his stay by another year to 2006 - however, Auxerre saw fit to cancel the agreement and this was later ratified by the French Olympic Committee.
The French star was upset with his club's reaction and has now voiced his opinions about the episode and confirmed he now wants to leave Auxerre.
Mexes is hoping his contract will be cancelled, because he feels Auxerre have reneged on their part of the deal.
It now remains to be seen what the outcome will be, although it seems unlikely that Mexes will have his contract cancelled - however a move away from the club does look the most likely outcome for the 21-year-old.
Arsenal are known to be very interested and are believed to have made moves over the past week to see whether Mexes would be available.
