Santos have revealed that they have started negotiations with AC Milan to sign Robinho in January.
The Brazilian club's president says that they have already sent "a written offer" to the Italian giants.
"Robinho wants to return to Brazil and for him that means returning to Santos," Luis Alvaro Ribeiro told TV O Povo de Fortaleza.
"We have presented a written offer, although there is a difference between what the player and the club are asking for.
"It can be circumvented but it is not a simple task. It is a battle that must have results by the end of this week."
Robinho played for Santos between 2002 and 2005 before leaving for Real Madrid.