Navas has been one of the stars of the FIFA World Cup where he is featuring for Costa Rica, helping his team to the quarter-finals by starring in a penalty shootout victory over Greece in the last 16.
The 27-year-old has conceded just twice in four matches in Brazil and continues his fine domestic form from last season, including a fine showing in Levante's 2-0 victory over Atletico in May.
The Spanish champions have apparently set their sights on a deal for Navas to replace Thibaut Courtois, who is to return to Chelsea after three years on loan at the Vicente Calderon.
Levante president Quico Catalan claimed that Atletico offered €6 million plus forward Leo Baptistao for Navas' services, but that offer was rejected.
Catalan has now told Atletico that Navas will only be sold if his €10m release clause is met, while also revealing there is plenty of interest in the former Albacete man.
"Keylor has a €10million release clause and we know that Keylor is worth more than that," Catalan told Spanish radio station Cadena Ser.
"All the teams that have made offers for Keylor know what the answer will be - the release clause.
Referencing Atletico's offer, Catalan explained: "€6 million plus Leo Baptistao is not €10million.
"Keylor is having a great World Cup and many clubs, foreign and Spanish, have shown their interest."
