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.
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," said Agnelli.
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 UEFA Nations League match against France before he tested positive and was forced to miss the 3-0 win over Sweden on Wednesday.
Juventus place squad in isolation after McKennie tests positive
Juventus placed their squad into isolation on Wednesday after USA international midfielder Weston McKennie tested positive for coronavirus.
"This procedure will allow all persons negative to the controls to carry out regular training and match activities, but will not allow contact with people outside of the group," a club statement said.
The Juventus players and staff were isolating at the club's hotel until last week after two staff members tested positive.