Speaking to The Mirror, Petit said: "Now, he (Sanchez) is a winner. His attitude and approach in every game is fantastic. I can see why Arsene wants to keep him.
"At the moment nothing is decided and I believe Sanchez is waiting to see what players are brought in before he makes up his mind about his future."
The 27-year old has one year remaining on his contract and will be able to walk for free at the end of next season.