Arsenal have completed the signing of Charlton Athletic defender Semi Ajayi, according to the player.
The 19-year-old centre-back joins the Gunners on a free transfer having completed a successful trial spell at the club.
The Nigerian signs a two-year contract with the North London outfit and is delighted to have made the move.
"Delighted to announce that I have officially signed for Arsenal FC," Ajayu wrote on Twitter. "Can't wait to see what the next two seasons here have in store for me.
"It was sad to end my 10-year spell with Charlton this summer but I can't speak highly enough of all of the wonderful people I met during my 10 years there and I wish all [them] the best for the future as I will always have a soft spot for the club and its fans."
Ajayi scored for Arsenal in a 3-0 win over Blackburn Rovers at the end of August.
