The 29-year-old has endured an injury-ravaged career at Arsenal, suffering from as many as 40 separate injuries during nine years with the club.
The France international played 124 games for Arsenal in that time but was restricted to just one first-team appearance last term, against Southampton in the third round of the Capital One Cup.
Diaby moved to north London from Auxerre in 2006 and was the longest serving player in the Arsenal squad.
He was omitted from the retained list submitted to the Premier League along with Japanese winger Ryo Miyachi who spent last season on loan at Dutch Eredivisie side FC Twente.
Theo Walcott will take over the mantle as Arsenal???s longest serving player but the England forward is yet to renew his contract which expires in 12 months.