Gunners boss Arsene Wenger has been put on red alert by Marseille's admission they will sell the France midfielder.
Despite tying down Nasri to a new deal until 2012, the French club have admitted their star player has a clause in his contract that would force them to sell him for ?2m.
Marseille president Pape Diouf revealed: "Samir could leave each season, if we receive an offer in between ?2m and ?6m.
"But we are trying to envisage things from another angle and our aim isn't to weaken our team."
Wenger is a long-term admirer of Nasri and with Alex Hleb on the verge of quitting the club, he has signalled his intention to sign a creative midfielder.
Nasri, 20, has already played seven times for his country and claims he would be open to offers from Europe's top clubs.
He said: "At the moment, I am not thinking about what I am going to do.
"But I will not leave for another French club, that is for sure.