The Portuguese forward says the fresh terms he has agreed at the Santiago Bernabeu will be his penultimate - not final - agreement as a professional footballer
Madrid announced they had renewed the Portugal international's contract until 2021 on Sunday, which would extend his stay at Santiago Bernabeu to 12 years and take him to the age of 36 if he sees out the duration.
But Ronaldo, who set his sights on further silverware over his next five years with Madrid, is sure this agreement will not be his last in football.
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"I would like to thank the Real Madrid president, the club, my team-mates, those who have helped me reach this stage," he said at a club ceremony marking his renewal.
"It's a very important day. I have said many times that I carry this club in my heart, it's part of me.
"In a very special moment of time in my life, I'm going to be here for another five years. It's not going to be my last contract, let it be known, but it's very special.
"My thoughts are I want to continue being the best. I want to wear this shirt with pride and I'm sure I'm going to continue contributing the same over the next five years as I have been, scoring goals and winning titles.
"I have to wait and see [about the date of my retirement]. Who knows what the future holds. Of course, I would like to end my career at this club. This is my penultimate contract. I want to be here for many years to come. I'm overjoyed."
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Ronaldo is the favourite to win a fourth Ballon d'Or title in 2016, a year which has seen him win European titles at club and international level.
That was his second Champions League with Madrid, with whom he has also won La Liga, two Copas del Rey, the Supercopa de Espana, UEFA Super Cup and Club World Cup.
Madrid president Florentino Perez paid tribute to Ronaldo's accomplishments with the club at Monday's event to celebrate his deal and hailed what he believes is a magical period for his side.
"You are a living legend at this club - the highest scorer in the club's history," he said to Ronaldo.
"You are unique, one of a kind. You scored over 50 goals in each of your last six seasons, looking at your successes last year you deserve to win the Ballon d'Or.
"It's a special day for Real Madrid. You never tire, you always want more and will be part of this club for many years to come.
"Cristiano, we share the same ambition, desire. You have agreed to sign a deal that will see you stay here until 2021. We want to continue to build this legend, we want to be together for many years to come."
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Perez added: "Over our 100-year history we have built a tradition in the club - a legacy which has been passed on from one generation to the next.
"A club with great footballers with players who have defended this club, like Alfredo di Stefano and Gente. They showed us the way and I am now addressing their heir.
"This is a glorious era for the club. Fans from all corners, fans who speak different languages and different beliefs support this club that has 11 European Cups - the most successful club in history."
Ronaldo has scored 371 Madrid goals in 360 appearances since signing from Manchester United in 2009.