The package is widely reported to include a down payment of 30 million euros (£27million), with an additional 6m euros (£5.2m) in performance-based add-ons at a later stage.
There are also suggestions Fabregas is prepared to waive the £4million compensation he would be entitled to for the remainder of his long-term Arsenal contract, as technically the player never asked for a transfer.
"We have been clear that we didn't want Cesc to leave and that remains the case," he said.
"However, we understand Cesc's desire to move to his home town club and have now accepted an offer from Barcelona.
"We thank Cesc for his contribution at Arsenal and wish him future success."
Barcelona anticipate no late hitches and have announced details of how Fabregas will seal his return to the club on Monday.
They stated, on their official website, that Fabregas will have a medical test at Barcelona Hospital at 8am (0700BST) before undergoing a further test at Barcelona's medical centre at 10.30am (0930BST).
At 12.30pm (1130BST) he is due to sign his contract, which will be followed by photo opportunities and, at 2pm (1300BST), a press conference with Fabregas.