Bellamy has been linked with a move away from Eastlands this summer but a move to his hometown club seems highly improbable.
"It is an impossible dream but sometimes in football the impossible happens," Borley told the South West Echo.
"On paper it looks impossible but you never know with these things. A lot of people would have said Manchester City loaning Robinho out to Santos would be impossible but that is exactly what happened. Effectively they sent him home.
"It would take a very generous Manchester City and a very lucky Cardiff City if it were to happen but we know how superb it would be, particularly for our supporters.
"But Craig is a Manchester City player and we respect that totally."