FILE - Workers rest near billboard showing Chinese President Xi Jinping, reading: "Welcome President," right, and billboard reading: "Nobody was hurt in my shift today," in front of the Zelezara Smederevo steel mill, in the city of Smederevo, 45 kilometers east of Belgrade, Serbia, on June 29, 2017. Chinese leader Xi Jinping's visit to European ally Serbia on Tuesday, May 7, 2024, falls on a symbolic date: the 25th anniversary of the bombing of the Chinese Embassy in Belgrade during NATO's air war over Kosovo. (AP Photo/Darko Vojinovic, File)