The centre-back said: "Southampton is a big club, because I see everything here. I see the organisation and every deal.
"We do things like the big clubs.
"It was not an easy decision to leave Lyon but after a discussion with the chairman and the manager it was an easy decision.
"I love to be part of this project and Southampton really wanted me.
"It was important for me to know that.
"English fans love football, they have passion - it is not the same in France. It really is something special here."
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