Manchester United and Barcelona tried to sign PSG's Marquinhos last summer, the Brazilian defender has revealed.
Shaun Wright-Phillips insists he is happy again at QPR after turning down "offers and opportunities" to move in January.
This season Tello has made 16 appearances in all competitions for Barca, having represented Spain at this summer's Olympics.
A Barcelona statement read: "Barcelona announce they have reached an agreement with the player Cristian Tello to extend his contract until June 30, 2016. His buy-out clause has been set at 10 million euros.
"The player will sign his contract on Monday, December 17, in the Barcelona offices."