After Los Che chiefs announced the possibility of both being sold, Manchester United were linked with a stunning double-raid in January for the Mestalla stars.
Valencia sporting director Fernando Gomez told Las Provoncias TV: "If there was a moment that arrived that we cannot stand it any more, then of course we must sell and they [Villa & Silva] would be sold.
"We made a great effort in the summer to keep them, but if the economic situation continues, then things could become very serious.
"Still it was a success for us to keep them, because there was some large money offered to us."
Gomez stopped short though of saying a fresh offer had already been submitted, as he added: "We have not received an official offer for either Villa or Silva. I only know what has been said in the papers."