Vermaelen is a Gunner after clearing his medical examination. He joins on a multi year contract for an undisclosed fee. It is reportedly in the region of £10 million.
Manager Arsène Wenger said:
"Thomas is a great signing for Arsenal Football Club, and we are all delighted that he is joining us. Thomas is a solid performer with good experience of Champions League and UEFA Cup football and is also a regular with the Belgium national team."
He also singled out Vermaelen for his versatility which should bode well for a defense that has seen a number of injuries which have forced Wenger to rejigger the back four. He also pointed to Vermaelen's no holds barred attitude which should bring some much needed steel to a defense perceived by many as soft.
"Thomas is primarily a left-footed centre back, but he's multi-functional and can also play at left back. He is strong technically with a positive winner's attitude and I have no doubt his arrival will strengthen our team. Thomas Vermaelen will be a huge asset to Arsenal."
As for Vermaelen, he relishes the prospect of playing in the "best league in the world".
"I'm just so happy to be joining Arsenal. This is a great Club with a world class manager, high quality players and a fantastic stadium. Everything is set up for Arsenal to be very successful for years to come and I joined this Club because I know Arsenal will be challenging for trophies."
Arsenal also lists him at 6' 0" and not 5'11". That extra inch is significant in the debate which ensued about Vermaelen being undersized for a central defender.
He will give his first interview this Sunday.