The former Milan defender has stressed that anything can happen in the future amid ongoing speculation linking him with the Catalans
The Blaugrana already showed an interest in signing the Brazil international last summer, but he eventually left the Serie A giants for PSG instead.
But after putting in a commanding display in the first-leg of les Parisiens' Champions League quarter-final with the Catalans, rumours have again linked the player with a move to Camp Nou and he has hinted he would be open to a possible switch.
"You can never close the door on something, because you don't know what will happen in the future. I am happy now, but you never know what will happen in the future," the defender told El Mundo Deportivo when questioned about a potential move to Barca.
"There were conversations between Barcelona and my agent last year, but I had already given my word to [PSG director] Leonardo. There's no way back once you've given your word.
"Everybody has dreams. I have been following Barcelona ever since I was a kid and they had players like Romario, Ronaldo and Rivaldo.
"Do I have a buy-out clause? I only just got here and I'm not thinking about that. But we all know that a solution can always be found."
The 28-year-old has a contract with PSG until the summer of 2017.