Milan have yet to commit to a new contract for injured striker Ronaldo after the Brazilian was ruled out for at least nine months following knee surgery.

The 31-year-old's deal runs out in June and although the European champions have said they hope he will play for them again, Ronaldo has not been guaranteed a fresh contract.

He underwent surgery on his left knee in Paris on Thursday after being carried off in Wednesday's 1-1 Serie A draw with Livorno, only his sixth appearance in an already injury-plagued season.

The three-times World Player of the Year sustained a similar injury while with Inter in 2000.

"We hope this very sad image on Wednesday is not the last we see of him on the field," Milan chief executive Adriano Galliani said.

"Ronaldo is still not 32 and even if I don't comment because I am not a doctor, I hope he returns to play and that he does so in our jersey. Ronaldo is perhaps the best player Brazil have had since Pele."

Milan coach Carlo Ancelotti was equally sympathetic and although he said the club would wait for him, there was no specific talk of a new contract.

"Now everything is in his hands. I am convinced Ronaldo will return to playing because football is his world and we will wait for him," Ancelotti told reporters.

"The first time he had this type of injury, to the left knee, he recovered perfectly. I don't see why he shouldn't manage this time."

Milan said earlier in the season that Ronaldo's contract would be renewed if the often-overweight striker recovered his fitness and form.