Serbian President Aleksandar Vucic was displeased by the way he was treated during World War I centenary commemorations in France, Serbian media reported on November 12.
At the November 11 Armistice ceremony in Paris, which brought together leaders from numerous countries, Kosovar President Hashim Thaci was behind the leaders of France, Germany, Russia, and the United States, while Vucic was placed in a separate stand on the opposite side.
Serbian media quoted Vucic as saying , "You can imagine how I felt," and adding that he had "a lump in the throat."
"I couldn't believe what I was seeing before me, knowing the sacrifice that the Serbian people made in World War I," he said.
Historians say that Serbia suffered more losses as a proportion of its population in World War I than any other country embroiled in the conflict.
French President Emmanuel Macron hosted his U.S. and Russian counterparts, Donald Trump and Vladimir Putin, among other leaders, at the ceremony marking 100 years since the end of the war.
Tensions remain high between Serbia and Kosovo, two decades after a war between Serbian forces and ethnic Albanian fighters.
Kosovo's independence from Belgrade, unilaterally declared in 2008, is recognized by leading Western powers but not by Serbia.
Macron visits Serbia next month, and Vucic promised a "grand" welcome for the French leader.
With reporting by AFP