Vincenzo Spadafora originally protested the Juventus star's decision to fly to Italy following his positive Covid-19 test while on international duty with Portugal, almost two weeks ago.
But now Spadafora has gone a step further, blasting Ronaldo as "arrogant" and claiming in an interview on TV station Rai 3 (reported via AS) that an investigation has begun through Italy's Federal Prosecutor's Office.
The politician and the footballer have been at odds since Spadafora criticised Cristiano Ronaldo for flying back to Italy, claiming that the ex-Real Madrid attacker was not given authorisation to travel by health authorities.
Ronaldo flatly denied that via an Instagram live video while in quarantine, claiming: "A gentlemen here in Italy, whose name I won't mention, said I didn't obey the protocol - that's simply a lie.
"I followed all the protocols and I will continue to follow them, my conscience is clear... Everything I did was authorised.
"We did everything the right way - leaving the [Portugal] team, in the air ambulance, arriving in Turin... I did not have contact with anyone."
Now the war of words has intensified with the Italian sports minister firing back: "Cristiano did not respect the protocol. There is an investigation by the Federal Prosecutor's Office to prove it."
Spadafora also reportedly accused the 35-year-old of being "arrogant" and "disrespectful". Usually two of CR7's strong points, we'd argue, but we're not sure a politician should be using this language about someone who may be being officially investigated by authorities for his actions during a pandemic.
Ronaldo has shared images and videos of himself during his subsequent period of isolation in Turin and seems to be free from the more serious effects of the virus and in excellent health.
He tested positive for Covid-19 for a second time last Thursday, despite showing no symptoms, so is yet to return for Juventus in Serie A.
Football fans are keen for Ronaldo to take the field in the Champions League on Wednesday, as his club host Barcelona and Lionel Messi in a hotly-anticipated group game. But that will depend on a test taken 24 hours before the game coming back negative.
Whatever happens in the short term, it will be interesting to follow Spadafora's claim that Ronaldo will be investigated to see if he did break Italian protocol - and if any punishment could follow a resulting charge.
All imagery: PA Images
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