Ronaldo isn't ready to put a date on his comeback.

Ronaldo hopes to prove his fitness to win a contract with Manchester City, though PSG and Flamengo are also keen.

"I will not fix any date, although ideally I will be back in January," said Ronaldo. "But I won't rush because it is very common in those who, like me, have been out for a long time to suffer some muscular injury.

"I'm still lacking many things, I need 20-30 per cent to recover all my strength."