The 23-year old forwards future with the Gunners continues to be questioned as he stalls on signing a new contract and skipper Vermaelen fears he could be on his way out at the end of the season.
"Of course we want him to stay, but that is something that is going on between the player and the club,” the Belgian defender said.
“I don't know what is going on behind the scenes - we don't talk about it, because that is going on in football all the time.
"It happened last time with Robin (van Persie) in the summer. It's the job of the board and the club what they are going to do with it so we can't do anything about it.
"Theo has been invaluable for us when he played this year. He is dangerous for us, can stretch a team with his pace and I hope he could stay this year."