"I spoke with (Madrid sporting director) Pedja Mijatovic and with (Madrid president) Ramon Calderon and they told me that Robinho has to stay, that he cannot leave.
"So we cannot do anything because he has two years on his contract with Real Madrid," Ribeiro was quoted as telling Onda Madrid.
"Robinho never said that he is not happy at Madrid, but the fact is that he has a more interesting economic offer, that's all.
"Yes, I have to say that until August 31 anything is possible, until the transfer market closes we do not give this matter up as closed.
"The president Ramon Calderon has promised Robinho that if the club is presented with an offer of 40 million euros he will be allowed to leave."