The Gunners head to America today for four pre-season friendlies, the first of which will see them take on MLS side the Colorado Rapids.
But manager Unai Emery won’t be able to call on the services on Koscielny, who has refused to travel Stateside.
“Laurent Koscielny has refused to travel to the US for our pre-season tour,” a club statement read. “We are very disappointed by Laurent’s actions, which are against our clear instructions.
“We hope to resolve this matter and will not be providing any further comment at this time.”
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