According to the Daily Star, 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.
For the first time, United found their Spanish rivals prepared to negotiate after the player told them he would be interested in returning to England, the report said.
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 Bernabeu, which has just two years left to run, the report added.
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