The France international has scored six goals in 86 appearances after moving from Ligue 1 outfit Lorient to the Gunners in July 2010.
Koscielny was ever-present during Arsenal’s campaign last season, and forged a successful defensive partnership with Vermaelen as Arsène Wenger’s side finished in third place in the Premier League.
“I heard the news that Laurent extended his contract and I’m really happy,” Vermaelen told Arsenal’s website.
“From the start when he came to Arsenal he has shown he is a great player and he is developing really well. I think he has done everything for the club already and I hope he will stay a few more years.
“Of course he is not here at the moment because he is not fit – he had a holiday because he played in the Euros. But he is a great player and I’m happy that he signed for the club.”
Koscielny was part of Laurent Blanc’s 23-man squad for Euro 2012, with the Arsenal defender playing a part in France’s 2-0 defeat by Spain at the quarter-final stage.
On Tuesday, the Gunners revealed the centre-half had signed a new “long-term” deal at the north London club, although no details about the length of the contract were disclosed.
“Laurent has been outstanding for us over the last two seasons,” said Wenger.
“When you consider that until 2009 he was playing in Ligue 2 in France and that he is now performing at the very top level in the Premier League and for his country, the development that he has shown has been absolutely exceptional.
“Laurent is a top-class player and I am very pleased he has decided to commit his future to the club.”
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