The France international is currently sidelined with a serious knee problem, which is expected to keep him sidelined for up to 12 months.
Koscielny ruptured his cruciate ligaments during Arsenal’s 2-1 loss to Spanish side Atletico Madrid in the Europa League semi-final at the end of the 2017-18 season.
The 32-year-old missed the World Cup in Russia due to the knee problem to miss out on glory after France were 4-2 winners against Croatia in the showpiece.
Arsenal have appointed Spanish head coach Unai Emery as their new manager after Arsene Wenger stood down following 22 seasons in charge of the north London side.
The former Paris Saint-Germain manager has wasted no time improving his defence with the addition of Borussia Dortmund’s Sokratis Papastathopoulos and Juventus veteran Stephan Lichtsteiner.
And Koscielny, who has two years left to run on his current Arsenal deal, confirmed that he will leave the Gunners at the end of the 2019-20 season.
“I’m under contract until June 2020. Afterwards? I’m thinking of moving on, but I do not know where,” Koscielny told Nice-Matin.
“This is not relevant anyway! I am in England, my family too. Then there will inevitably be a lot of question marks.
“The bottom line is to have health. I learned to revitalise because there are so many more serious things in life.”
Arsenal finished in sixth place in the Premier League table last season to miss out on a Champions League spot.
The Gunners have also signed Lucas Torreira, Bernd Leno and Matteo Guendouzi this summer.
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