A Spanish state prosecutor accused the 32-year-old of failing to pay €14.7 million in unpaid taxes on image rights earned between 2011 and 2014.
According to Spanish media outlet Marca, while the club understandably want to keep the player, they have set Ronaldo's transfer fee at €180m (£157m).
However, Ronaldo has dismissed all the reports and accusations made against him.
Another source close to the star player told the BBC that "he feels he's honest, has good character and did everything OK".
"The relationship in Madrid wasn't the best but that doesn't mean he doesn't want to go back to Manchester where he is very grateful of what happened", the 66-year-old added.
A source claims the Portugal worldwide "feels great indignation" with the speculation about his tax affairs and and a sense of "injustice" at the allegations - which he contests - and has made a decision to leave Spain.
Current manager Jose Mourinho and Ronaldo ended on bad terms at Madrid and Fergie may be the only one to heal the wounds.
Ronaldo maintains his innocence in the tax evasion case and insisted that did everything in accordance with Spanish law. Despite Real Madrid winning countless champions league trophies, La Liga trophies CR7 still wants to leave?
Scoring for Real Madrid in the recent Champions League final win over Juventus.
At this moment in time Ronaldo, who's Real Madrid's all-time leading goal scorer, is preparing to represent Portugal at this summer's Confederations Cup being held in Russian Federation.