Athletic Bilbao are demanding Manchester City meet Javi Martinez's buyout clause.
Bilbao have told Manchester City to forget about trying to sign Martinez for less than his £31.7million release clause.
The Basque club have so far fended off intense interest in the midfielder-cum-defender and his Spain team-mate Fernando Llorente.
They have already scared away Barcelona, who turned to Arsenal's Alex Song after being priced out of a move for Martinez, but City and Bayern Munich remain in the race for the 23-year-old.