Arsenal are "hugely concerned" about Henrikh Mkhitaryan missing the Europa League final against Chelsea because of the continuing tensions between Armenia and Azerbaijan.
The Armenia captain skipped the Gunners' earlier fixture in the competition against Qarabag in Baku because of the issue, which has flared up once again with the Azerbaijani capital hosting the final.
Hostility remains between the neighbouring countries over the disputed Nagorno Karabakh region, where a ceasefire was declared in 1994 after fighting erupted several years earlier.
Those issues meant Mkhitaryan did not travel with Borussia Dortmund to a Europa League tie against Gabala in October 2015. Arsenal say they need assurances over his welfare before naming him in the squad for the May 29 final with Chelsea.
The club said: "The safety and security of our players is of paramount importance.
"We are seeking guarantees from UEFA that it will be safe for Henrikh Mkhitaryan to travel to Baku for the Europa League final.
"Acceptable guarantees have not been received yet. We hope UEFA will be able to supply these promptly.
"We are hugely concerned the location of the final could lead to Micki not being able to play in a European final."
Arsenal reached the final by beating Valencia.