Ronaldo left the field in tears after Portugal were knocked out of the Qatar 2022 World Cup at the quarterfinal stage by Morocco on Saturday.
At 37 years of age, Ronaldo will be well into his 40's by the time the next World Cup rolls around in 2026.
Ronaldo is a veteran of five World Cups and became the first player to score in as many tournaments when netting against Ghana in Portugal's opening game in Qatar.
The five-time Ballon D'or winner was restricted to the role of a substitute in Portugal's last two games in Qatar.
Having led his country to European Championship and Nations League glory in 2016 and 2019 respectively, Ronaldo has conceded he will not be able to add the Word Cup to his list of laurels with Portugal.
"Winning a World Cup for Portugal was the biggest and most ambitious dream of my career," he posted on Instagram.
"Fortunately, I won many titles of international dimension, including for Portugal, but putting the name of our country on the highest level in the world was my biggest dream.
"I fought for it. I fought hard for this dream. In the five tournaments I scored in over 16 years, alongside great players and supported by millions of people, I gave my all.
"I left everything on the field. I never turned my face to the fight and I never gave up on that dream. Unfortunately, yesterday the dream ended."
"It is not worth reacting hot," Ronaldo added on his international future.
"Much has been said, much has been written, much has been speculated, but my dedication to Portugal has not changed for an instant.
"I was always one more person fighting for everyone's goal and I would never turn my back on my team-mates and my country.
"For now, there's not much more to say. Thank you, Portugal. Thank you, Qatar. The dream was beautiful while it lasted.
"Now, it's time to be a good advisor and allow each one to draw their own conclusions."