Alfa Romeo team principal Frederic Vasseur says "we look forward to further advancing his skills in support of his progress as a racing driver." Switzerland-based Sauber rebranded its F1 name as Alfa Romeo earlier this year.
The team was called Alfa Romeo Sauber when it finished eighth in the constructors' standings last year. Charles Leclerc's impressive performances in his debut F1 season earned him a move to Ferrari.
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