Leaked U.S. Intel Accuses Serbia of Secretly Arming Ukraine Despite Russian Ties

According to leaked Pentagon documents, Serbia has supplied weapons to Ukraine despite close ties to Russia and official neutrality.
Serbia's defense minister denies sending weapons but leaves open the possibility they ended up in Ukraine without government's knowledge.
The leaked documents claim Serbia agreed to send lethal aid to Ukraine, making it the only European country not sanctioning Russia to support Ukraine militarily.
The leak has caused diplomatic tensions as the U.S. tries to verify the documents' authenticity and determine the source of the breach.
If true, Serbia risks isolation from the West which demands it normalize relations with Kosovo before joining the E.U.