Since the start of the month, the Portuguese superstar has been linked with a transfer away from Old Trafford due to his desire to play in the Champions League.
However, as it stands, remaining at United appears to be the most likely outcome, partly due to the likes of Chelsea and Bayern Munich not being interested in a deal for the 37-year-old.
Furthermore, head coach Erik ten Hag has stated that he wants to keep Ronaldo in his first-team squad, despite the continued absence of the player due to personal reasons.
Speaking to reporters on July 11, the Dutchman said: "I am looking forward to working with him. Cristiano is not for sale. He is in our plans. We want success together. I had a good talk. That is between Cristiano and me. What I can confirm is we had a really good conversation together."
Nevertheless, a report in AS says that Atletico and Ronaldo are interested in working together during 2022-23.
The report claims that head coach Diego Simeone is ready to give the green light for a transfer to materialise should it become a financial possibility.
As it stands, Atletico are said to require a number of sales to take place before they can entertain trying to facilitate what would be one of the most eye-catching transfers of the summer.
The La Liga side would have to raise at least €40m (£33.91m) in order for Ronaldo to make what would be a controversial switch to Wanda Metrpolitano.
He has already spent nine years of his career representing Real Madrid, contributing a remarkable 450 goals from 438 appearances for Los Blancos.
Two La Liga titles and four Champions League crowns were won during his stint at the Bernabeu, and it is unclear whether the player would be prepared to take a substantial hit to his legacy by playing for the club's rivals.
Nevertheless, the report says that Ronaldo is "seduced" by the idea of playing for Simeone, who already has Joao Felix, Antoine Griezmann and Alvaro Morata as his attacking options.
Ronaldo, who scored 24 goals for United last season, still has a year left on his contract, with the option also there for his contract to be extended through to 2024.