La Liga's table-toppers, along with several Premier League clubs including Liverpool and Arsenal, have been linked with the 23-year-old six-time France international, whose contract with PSG ends in June.
Reports in France and Spain claim Barca are preparing to offer Rabiot a five-year deal when the transfer window opens tomorrow.
The Catalan club said in a statement on Sunday they had made contact with PSG's management "last August and then a week ago" to express their interest in Rabiot, but had not spoken to the player.
The statement read: "In response to the news that has appeared in France, Barcelona state that there has been no breach of regulations regarding the signing of PSG players.
"The only contact was made last August and then a week ago. In both case, the contact was made with the sporting managers of PSG in order to express Barcelona's interest in the player Adrien Rabiot. "Barcelona always want to work with the highest level of transparency with PSG and any other club. Barcelona deny the existence of any type of agreement with PSG players Adrien Rabiot."