Valencia are unwilling to sell star striker Roberto Soldado to Tottenham unless his €30million release clause is met.
The English Premier League outfit are eager to add to their options up front to avoid relying on Jermain Defoe and Emmanuel Adebayor, who has been linked with a move.
Spurs manager Andre Villas-Boas is reportedly interested in securing the services of Aston Villa star Christian Benteke after the Belgian requested a transfer on July 8.
Valencia president Amadeo Salvo confirmed Tottenham had made a bid for 28-year-old Soldado but the La Liga club would like to see the Spanish forward's release clause met.
"The English team knows the situation. Valencia needs money," Salvo said.
"But we don't have to sell our best player."
Tottenham have brought in Paulinho for £17m in the off-season but want to add a forward with long-term target Leandro Damiao unlikely to leave Internacional.
Internacional president Luis Cesar Souto hopes Damiao's value will increase if the 23-year-old performs well at the 2014 World Cup.
"It's silly to sell," Souto said.
"We're confident and we understand that he can wait another year, play the World Cup, increase his value and then be transferred."
Tottenham almost signed Damiao in January but failed to close out a deal and were expected to bring him to White Hart Lane in the off-season.