The Rio de Janeiro outfit's vice-president, Sandro Lima, said Monday an informal offer had already been made for the 34-year-old, reports Xinhua.
"We have already sent Riquelme some figures," Lima said. "There are some other details that need to be discussed before we can say we have made a definitive proposal.
"We are taking our time. It depends more on where he wants to play. We know that there are other clubs interested too."
Riquelme has not played since quitting Argentine giants Boca Juniors in July last year after a 1-3 aggregate loss to Brazil's Corinthians in the Copa Libertadores final.
Lima said Fluminense would not need to negotiate with Boca after the Buenos Aires outfit agreed to terminate the former Villarreal and Barcelona star's contract by mutual consent.
