Arsenal boss Wenger admits decisions needed over off contract defenders
Gallas' deal expires this summer and while negotiations are continuing over a new contract, there has been no agreement yet.
He told arsenal.com: "I still have to assess the Gallas and Campbell situations. Silvestre is out of contract too and the whole package has to be right - one goes, one stays. We have to get the number right.
"If Gallas and Campbell stay it will depend slightly on how well Djourou comes back about what we will do. He looks good in training, quite positive."