Euro 2016 champions Portugal will begin their campaign at the tournament on Tuesday in their Group F clash against Hungary at the Puskas Arena.
Ronaldo, who is set to become the first player to compete at five Euros, attended a press conference alongside Portugal manager Fernando Santos.
However, the 36-year-old Portuguese forward appeared bemused when he took his seat and spotted the Coca-Cola in front of him.
Ronaldo rocked back and forth in his chair before he decided to pick up the two Coke bottles and slid them away from him.
The five-time Ballon d'Or winner then proceeded to lift a bottle of water in the air and appeared to say 'agua,' which is Portuguese for 'water.'
Coca-Cola has partnered with Euro 2020 organisers UEFA as part of its sponsorship of the European competition.
Ronaldo previously admitted that he was 'irritated' by his son Cristiano Jr drinking Coke and eating crisps.
Cristiano Ronaldo was angry because they put Coca Cola in front of him at the Portugal press conference, instead of water! :joy:
He moved them and said "Drink water" :laughing:pic.twitter.com/U1aJg9PcXq
- FutbolBible (@FutbolBible) June 14, 2021
Speaking at Dubai's Globe Soccer Awards in 2020, the Portugal captain said: "We'll see if my son will become a great footballer.
"Sometimes he drinks Coke and eats crisps and it irritates me, he knows that.
"Sometimes I tell my son to take a dip in cold water to recover after a run on the treadmill and he says, 'Dad, it's so cold there.'
"That's fine, he is only 10 years old."
Manchester United legend Ryan Giggs was furious when a young Ronaldo turned up with a can of Coke at breakfast, according to one of Ole Gunnar Solskjaer's former teammates.
The 47-year-old Welshman later responded to the rumours by saying that he was 'unsure' if he pinned Ronaldo to the wall over the Coke incident.
Portugal are in Group F, AKA the 'Group of Death,' alongside Hungary, Germany and 2018 World Cup champions France.
Featured Image Credit: PA/Twitter
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