'Yes, I think so, if there hadn't been any specific authorisation from the health authority.'

Cristiano Ronaldo may have broken health rules when he returned to Italy after testing positive for COVID-19 in Portugal, Italy's sports minister said on Thursday.

The Juventus forward flew back to Italy in a private jet on Wednesday to go into quarantine at home.

Vincenzo Spadafora, the sports minister, was asked during a radio interview if Ronaldo might have broken health rules in doing so and he replied: "Yes, I think so, if there hadn't been any specific authorisation from the health authority."

Juventus president Andrea Agnelli said no rules had been broken.

"You must call the Ministry of Health and the Ministry of the Interior and have them explain what has been violated," Agnelli said during a news conference.

Juventus said on Wednesday that Ronaldo had returned on a medical flight "authorised by the competent health authorities".

Ronaldo played a friendly against Spain and a Nations League match against France before he tested positive and was forced to miss the 3-0 win over Sweden on Wednesday.