Quaresma's agent, Jorge Mendes, has been in Spain this week talking with interested clubs, according to local press reports.
But Porto president Pinto Da Costa has quashed all speculation, telling Portuguese Broadcaster SIC Noticias: "We will not sell him. This is a guarantee.
Madrid have also been sniffing around Lucho Gonzalez and again Da Costa was quick to clarify his position on another of their prized assets.
"To make clear that we did not want to sell him [Lucho Gonzalez] I said that I would sell in exchange with [Ruud] van Nistelrooy," said Pinto of the Argentinian.
"They replied that the striker would not leave and I said okay, we are tied then."