The 37-year-old has told United that he wants to leave Old Trafford this summer in order to join a club who can challenge in the Champions League.
Ronaldo is also said to be disillusioned with United’s approach to the transfer window and has recognised that both Manchester City and Liverpool have already strengthened.
The Portugal international still has one year remaining on his current contract and United initially told the forward that they do not intend to sell him.
But according to UOL, United’s hierarchy, with the endorsement of new manager Erik ten Hag, would be willing to sell Ronaldo for around £13m.
Chelsea have been offered the chance to sign Ronaldo this summer and it’s understood that he would be open to a move to Stamford Bridge.
But while Chelsea’s co-owner Todd Boehly is open to the move, Thomas Tuchel would also need to be convinced that Ronaldo’s arrival would fit into his plans.
Ronaldo was due to return to pre-season training with United on Monday but he remained in Portugal due to ‘family reasons’.
He is also not expected to travel with United’s squad for their pre-season tour of the Far East and Australia.
United’s players are due to fly to Bangkok on Friday, while their first fixture is against Liverpool next Tuesday.
Ronaldo’s agent, Jorge Mendes, has been contacting potential buyers but several clubs have already ruled themselves out of the running including Real Madrid and Bayern Munich.
On Wednesday, Bayern’s CEO Oliver Kahn said: ‘As much as I appreciate Cristiano Ronaldo as one of the greatest, a transfer would not fit into our philosophy.’
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