The Catalan giants have a slight edge as Fabregas was born there and learned his trade at the Barca academy before moving to Arsenal in 2003.
Yet Madrid president Florentino Perez is making Fabregas his No 1 target for next summer.
And Perez has a fierce reputation when it comes to getting his man - having lured most of the world's major stars to the Bernabeu in his two stints as president during the last decade.
But Wenger snapped: "The speculation comes from Spain, not here. We've always had the same speech about that.
"What they speak about in Madrid or Barcelona, how can we influence that?
"If one day we want to sell a player - and those clubs are interested - they can call us.
"They don't need to go through a newspaper. We're not ready to sell any of our players."