Ronaldo refused to commit his future to Real Madrid after helping the Spanish champions land their third successive Champions League title in May.
The Portugal international has reportedly since rejected the chance to sign a new contract at the Bernabeu, with his agent Jorge Mendes said to be plotting a move away from the Spanish capital.
Manchester United have been linked with a move for their former player, but Juventus are now believed to be in the driving seat as the Italian champions look to secure what would be a spectacular deal.
According to Marca, Juventus are prepared to offer Madrid £106m for Ronaldo, while the Italian champions have already put together a wage package in the region of £500,000 a week.
Ronaldo has scored 450 goals in 438 games for Los Blancos, but his relationship with club president Florentino Perez has deteriorated over the last 12 months.
The 33-year-old was a part of the Portugal side that were eliminated from the 2018 World Cup on Saturday night courtesy of a 2-1 defeat to Uruguay in the round of 16.