Arsenal have beaten north London rivals Tottenham Hotspur to the signing of William Saliba in a deal reportedly worth around £27 million (A$48 million) that will see the teenager return to Saint-Etienne on loan.
Saliba said Arsenal are "the biggest club in England" and that is why he chose the Gunners over Premier League rivals Tottenham.
He completed his move to Arsenal on Friday morning, but the 18-year-old will remain with the Ligue 1 side on loan during the 2019-20 season.
Arsenal were long seen as frontrunners to sign the highly-rated centre-back, with north London foes Tottenham making a late bid to beat Unai Emery's team to his signature.
But Saliba wasted no time in endearing himself to the Arsenal faithful by explaining why he decided to join the club instead of Spurs.
"First of all, it's a massive pleasure to sign for a really, really big English club," Saliba told Arsenal's official website.
"This is the biggest club in England for me, so it was an easy decision. I didn't think twice about signing here, so I'm really happy.
"The history, the badge... since I was little, I've been watching Arsenal play in the Champions League and so on, and there are a lot of French players who have come through here. So that really helped me to make my mind up.
"I spoke to Matteo [Guendouzi, the Arsenal midfielder]. I even bumped into him at a funfair in Paris, and that's where I told him that Arsenal wanted to sign me! He gently advised me to come here and explained what it was like."
The 18-year-old becomes Unai Emery's third signing of the close season after the capture of young Brazilian forward Gabriel Martinelli and Real Madrid's Dani Ceballos.
Arsenal head coach Emery told the club's website: "We’re delighted William is joining us. Many teams wanted him but he decided he wanted to come to us and be part of our future.
"He will stay in France next season for more experience and then we look forward to him joining our group."
Saliba feels it is the right move to remain with Saint-Etienne for another season before testing himself in the Premier League.
"Well, it was important first of all because I wanted to prove myself for another year at Saint-Etienne, before I come to try and establish myself here at Arsenal," he said.
"This is a big club, and when you come here, you need to be ready. So I'm going to try and have a great season with the club that developed me in order to be ready for Arsenal."
Saliba posted a video announcing his Arsenal arrival on Instagram, the clip quickly going viral.
The flashy video included shots of a private jet, a Lamborghini and Saliba's agent during various stages of the journey, medical and club media duties.