William Saliba says Arsenal are the biggest club in the England.
The 18-year-old has completed a 27m move from Saint-Etienne, where he will return for the 2019/20 season.
Tottenham had offered to buy the Frenchman, but Saliba decided to join the Gunners instead.
Explaining the decision, Saliba said: "It's a massive pleasure to sign for a really, really big English club. 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.
"You have to keep working when you hear that a club is interested in signing you. You have to keep working; that's what I'm doing and I'm proud to be signing here."
