The Spain international is believed to be one of a few big players on their way out of the Nou Camp after a disappointing season, with the club set to undergo major changes.
Although Barca are not likely to force their playmaker out of the door, they are willing to listen to offers in the region of £40m, with interest strong.
Arsenal and United are two sides that are particularly keen, and could take advantage of the situation.
The Red Devils have just appointed Louis van Gaal as their new manager, and the Dutchman is said to have around £150m to spend in order to repair the club’s ailing squad after disastrous season.
He is believed to have targeted a creative midfielder, with Fabregas possessing the desired attributes.
Arsenal are also in the battle due to their close relationship with the player.
The Gunners snapped up the World Cup winner as a teenager before selling him back to his boyhood club in 2011.
Fabregas may well be followed out of Barca by Alex Song, Alexis Sanchez, Cristian Tello and Pedro.