The Daily Express says Quintero can only leave for his £32 million buyout clause.
Porto have received no offers as it stands for the sought-after attacking midfielder.
The Portuguese giants are only expected to sell if a massive transfer fee is made for the star.
Quintero's agent said: "There are clubs interested, there is much interest in the player, the clubs in Spain and England, but to leave would be one willing to pay the termination clause of the club."
It was reported earlier this week that the Colombian would fly to north London later this week to confirm a £16million deal,
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