"I am very happy with this agreement," said the 25-year-old on the official Sao Paulo website, having been on a rehabilitation programme with the side for two months.
Inter were not mentioned in his comments, but agent Gilmar Rinaldi assures he will return to San Siro after June 30.
"We have worked things out. There are only a few details to be finalised, but everything is decided for a loan spell until June, then he will return to Inter," said Rinaldi after a meeting with President Massimo Moratti and technical director Marco Branca.
It will be a free loan spell, but after initial reports that Inter would pay his wages, it seems Adriano will be effectively employed by Sao Paulo.
"It will be a sum of money that is within Sao Paulo's wage policies, especially as his recovery is still in progress," insisted director general Joao Paulo de Jesus Lopes.