The same club also signed Moussa Sow from Fenerbahce on a big money move last season.
Nani still has another two-years remaining on his contract but has been linked with a move away from the Istanbul giants after reportedly falling out with head coach Vitor Pereira.
Nani has also attracted interest from Inter Milan, Everton and Valencia who could all activate his €8 million release clause.
Al Ahli would however, have to pay a higher fee as his release clause is only open to clubs from European major leagues – Premier League, Seria A, La Liga.
Nani will not make a decision on his future until after Euro 2016. The experienced winger is currently on international duty and has one goal in two games for Portugal in Group F.