A transfer fee has been agreed between the Gunners and the Catalan giants after much speculation over the future of the Cameroon international
The Blaugrana have been keeping tabs on the 24-year-old and the Gunners have confirmed that they have accepted an offer from the Catalan giants.
Song will make his way to Spain to discuss personal terms and complete a medical.
The Cameroon international established himself as a key member of Arsenal's midfield last season, and looks like being the second high-profile exit from north London this week, after the transfer of striker Robin van Persie to Manchester United was confirmed on Friday.
Meanwhile, Arsene Wenger's side kicked off their Premier League campaign with a frustrating 0-0 draw at home to Sunderland as it looks to rebuild its squad for a title push.
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