The pair enjoyed success with Valencia.
Silva smiled: "David Villa. I just know he's a world-class striker. We have a lot of superstars already but there is always room for one more like him.
"If there was one more to arrive it would be brilliant to sign someone like him - a really huge signing.
"He scores a lot of goals, we had a great understanding from all those years together at Valencia - I rate him so highly.
"We've stayed in touch, we are often texting or talking on the phone. He likes it at Barcelona but I've been telling him how much I am enjoying life in England."