The Daily Star says United and Real Madrid have spent the past 12 days negotiating an £80m package – and the Premier League champions are increasingly confident of getting their man.
David Moyes made his move two weeks ago when the club heard through the grapevine Madrid had stepped up their interest in signing Gareth Bale.
And for the first time they found their Spanish rivals prepared to negotiate after the player told them he would be interested in returning to England.
New United chief executive Ed Woodward made contact with Real president Florentino Perez in the knowledge Ronaldo had yet to agree and extension to his current deal at the Bernabau which has just two years left to run.
United have been happy to talk openly about their interest in Barcelona midfielder Cesc Fabregas, with speculation surrounding that transfer meaning work on the Ronaldo move could be done without fuss in the background.