Some reports suggested that 27-year-old Grand Tour star could be breaking his contract early after a falling out with WorldTour team Movistar.
"My next commitment will be to represent Colombia in the 2017 Bergen Worlds," Quintana wrote on Twitter. "In 2018, I will ride with the Movistar Team in the Tour de France."
He posted the note and a photograph from Colombia, where he returned after the Tour de France. He will return to Europe for the world championships in Bergen, Norway, on September 24.
This year's Tour was the worst for Quintana. After already placing second twice and once third, always behind winner Chris Froome, he rolled into Paris in 12th overall while Froome collected his fourth yellow jersey.
He battled with Dutchman Tom Dumoulin (Sunweb) until the end and lost the leader's pink jersey to him on the last day in Milan.
Italian newspaper La Gazzetta dello Sport reported this month that he and the team fell out shortly after the Giro finished.
Quintana wanted to return home to train in Colombia and the team wanted that he stay in Europe, which he did.
The article also said that general manager Eusebio Unzué preferred that Quintana only race the Tour in 2017 and not the double. Other reports said otherwise.
Quintana's father Luis said, "Colombians are protesting because [team Movistar is] burning up Nairo. He should not have raced the Giro if he was going to race the Tour.”
Movistar, according to the article, was letting Quintana out of his contract early. His current deal runs two more years, through 2018 and 2019.
Team Astana, which is due to lose Fabio Aru to team UAE, reportedly wanted to sign Quintana as a replacement. Sky, according to one earlier report in July, also wanted the talented climber.
"No, it's not true," Quintana's agent Giuseppe Acquadro told Cycling Weekly. "Yes, the other teams would want him, there's interest, but he has a contract.
"Quintana is important for Movistar the sponsor, which has a huge South American market.
"Also, Nairo was not at his best this time but you watch, he could still return to win the double one year. I think it's possible."
Movistar this month signed Mikel Landa from Team Sky for the 2018 and 2019 seasons.
The Basque rider won a stage in the Giro and the mountains classification and returned to the Tour to help Froome to his victory.
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