Cesc left the Gunners for Barcelona last summer.
"I still speak to Cesc quite a lot," Wilshere told the London Evening Standard. "He texted me the other day after my operation and he texted me well done about the baby, too.
"It [the link with Barcelona] had been going on with Cesc for a couple of years now so I guess we always knew he would go at some point.
"Especially this year, Cesc wanted to leave and when a player wants to leave, the boss did the right thing. He'd been great for us and was one of our best players for the last six years.
"If you look at him now, he's flying. It'd be nice if he came back one day - the door is always open for him because of what he did at Arsenal.
"You'd almost say he's an Arsenal legend now and I think the fans would welcome him back as well."