The 37-year-old attacker has informed the Red Devils’ hierarchy that he wants to leave the club this summer and does not believe they are in a position to challenge for silverware.
Ronaldo, who is not keen to spend a season outside of the Champions League at this stage of his career, missed pre-season training on Monday after being given permission to stay in Portugal due to family reasons.
He has already been linked with a host of clubs, including Sporting Lisbon, Roma, Bayern Munich and Chelsea.
But now a new, shock name has emerged, with Spanish newspaper AS reporting that super-agent Mendes has been meeting with Barcelona president Laporta – and Ronaldo’s name was part of the discussions.
The pair met on Monday evening for dinner and the prospect of signing Ronaldo – who, of course, enjoyed a remarkable career with Real Madrid – was on the agenda, with Barcelona having explored the possibility a year ago too.
Back then, Barca wanted a star name to fill the void left by Lionel Messi – who opted not to renew his contract and signed for Paris Saint-Germain – but they were not in a position for afford Ronaldo.
The situation may have changed now, though, with Barcelona raising funds by selling off television rights and part of its merchandise arm.
They had been targeting a move for Bayern Munich striker Robert Lewandowski, but, despite his pleas to be allowed to leave, the German club are unwilling to sell and are demanding a transfer fee of around £50million – even though he only has one year left on his deal.
Although Ronaldo would command a massive salary, he could be a more affordable option than Lewandowski if United agree to waive a transfer fee.
United, though, want to recoup as much of the £21.4m fee they paid to Juventus as possible.
It remains to be seen if Laporta will initiate a move for Ronaldo and he and Mendes discussed several other players during their meeting, with Bernardo Silva, Ruben Neves and Rafael Leao also on Barca’s radar.
The prospect of Ronaldo moving to Camp Nou would send shockwaves through the football world, with the five-time Ballon d’Or winner having spent nine seasons playing in the white of Real, scoring 450 goals in 438 appearances in all competitions.
For more stories like this, check our sport page.
Follow Metro Sport for the latest news on
Facebook, Twitter and Instagram.