Monegasque rookie Leclerc, a 20-year-old Ferrari protege, made his debut with Sauber this season after winning last year's Formula Two title.
Finland's 2007 Formula One World champion Kimi Raikkonen will leave Ferrari at the end of the season in a swap with Sauber's Charles Leclerc, both teams announced on Tuesday.
Monegasque rookie Leclerc, a 20-year-old Ferrari protege, made his debut with Sauber this season after winning last year's Formula Two title.
"Scuderia Ferrari announces that, at the end of the 2018 season, Kimi Raikkonen will step down from his current role," Ferrari said, later also confirming Leclerc's arrival.
"As a world champion for Scuderia Ferrari, he will always be part of the team’s history and family. We thank Kimi for all of this and wish him and his family a prosperous future."
Raikkonen posted a message on Instagram announcing he would be rejoining Sauber on a two-year deal.
The Finn first drove for Sauber in 2001.
"Guess who’s back?! Next two years with @sauberf1team ahead! Feels extremely good to go back where it all began!" the 38-year-old told his 974,000 followers.
The move was later confirmed by Sauber in a separate statement.
"Signing Kimi Raikkonen as our driver represents an important pillar of our project, and brings us closer to our target of making significant progress as a team in the near future," said principal Frederic Vasseur.
"Kimi's undoubted talent and immense experience in Formula One will not only contribute to the development of our car, but will also accelerate the growth and development of our team as a whole."
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