Valencia president Juan Soler admits the club have asked Manchester United to name their price for Cristiano Ronaldo.
Soler, who today unveiled close season signings Fernando Morientes and Asier Del Horno from Liverpool and Chelsea respectively, now wants to stage a third raid on the Premiership.
'I have always said it will be difficult,' said Soler in remarks reported by Marca. 'But nothing is impossible.
'Until they tell us no several times we will not give up. At the moment it's a priority for our technical department and we have until August 31 (when the transfer window closes).'
The Portugal international winger has been linked with Real Madrid and has previously expressed a desire to play in Spain.
'First we will negotiate with the English club and then the player,' said Soler.
Meanwhile, Morientes, who missed out on a place in Spain's World Cup squad after a disappointing campaign with Liverpool, told club website: 'I don't want to dwell on the past but instead to work with my new team.
'Now I am at a different club and must change my tune.'
Del Horno, who won the Premiership with Chelsea last year, missed the World Cup through injury.
He said: 'It's been a great year. Playing in England has developed me as a player and now I can look forward to playing in the Champions League and the Primera Liga.'