Sterling was photographed in the Madrid-based sports daily AS with a City shirt on one shoulder and a Madrid shirt on the other.

The 25-year-old, who is under contract to City until 2023,  was very complimentary about the Spanish giants when asked, describing them as a "fantastic club".

"Right now I'm at City and I am very happy but I also have to say that Madrid is a fantastic club," Sterling said in the AS interview.

"When you see the white shirt, you know exactly what the club represents, it's enormous. But I must say that I have a great contract with City and I have to respect that."

City and Real meet in the first leg of their Champions League last 16 tie at the Bernabeu Stadium on Wednesday, so the timing of Sterling's interview has raised eyebrows.

Sterling is one of City's key assets and his future could be up in the air if the club fail in their appeal against a two-year ban from the European competitions for breaching UEFA's Financial Fair Play regulations.

But Guardiola is not worried about what Sterling said about Real.

"The players are free to talk and say what they think," Guardiola told reporters on Friday.

"We are not here to tell the players what they have to say. It is normal in the Madrid media to speak about Madrid."

Guardiola also has no concerns about the attitude and commitment of City's star players, including Sterling, over the last three months of the season.

He said he does not believe the FFP scandal will have any galvanising effect on his squad, He said that in his mind it is not needed, especially with City alive in both domestic cups and the Champions League.

"I'm completely sure about the commitment of our players," Guardiola said.

"It's about what they've shown for many years. Nothing changes, as at the end of the season nobody knows what is going to happen.

'I'm so proud'

"With calm, we will decide what we want but for the next three months the commitment will be incredible."

Saturday's Premier League trip to Leicester will be City's first away game since the FFP ban and his team could be in for a hostile reception.

Guardiola knows there is little chance of him changing people's opinion about his club, and that any success will be overshadowed by allegations of financial cheating.

"I cannot change that, but I know how hard we work and I'm so proud of what we've done these years we have been together.

"I have a different opinion, nobody has helped us outside. We did an incredible job day-by-day, game-by-game and nothing will change that opinion.

"But I repeat, it's (FFP) not finished, it's not over, we appeal and we will see what happens."

str/smg/pb