The Gunners captain is wanted by several clubs, including Barcelona.
Walcott told The Sun: "I don't know what is going to happen with Cesc. It's totally up to him but he has got a long time left on his contract.
"He wants to win things and it's difficult for him. But he is our captain and he means so much to the team and to our fans.
"He's won a World Cup and a European Championship. Having him in the dressing room is great for the younger generation and he'll help attract players to the club."