William Saliba will sign a five-year contract with Arsenal on Tuesday.
The Gunners have been chasing the signature of the Saint-Etienne centre-back and have seen off interest from north London rivals Tottenham Hotspur.
According to French radio station RMC, an agreement has been reached on the basis of €29m plus bonuses, with Saliba on his way to the Emirates Stadium.
It is claimed that the centre-back's desire to join Arsenal over other interest has been key in the Gunners winning the race.
Saliba will now put pen to paper to a five-year contract with the Gunners on Tuesday.
As per the terms of the agreement, he will then be loaned back to Saint-Etienne for the entire 2019/20 season.
Arsenal are sure to be delighted at having won the race for the highly rated centre-back, however they will have to wait 12 months to welcome him into the squad at the Emirates Stadium.
Saliba will now look to kick on with his development in familiar surroundings and head to Arsenal next summer an even better player.
