The head of the Ukrainian football association has caused outrage in Russia by unveiling a new national team shirt emblazoned with a map of Ukraine that includes Crimea.
Russia annexed Crimea from Ukraine in 2014. Moscow considers the peninsula part of Russia, but it is internationally recognised as part of Ukraine.
The front of the yellow shirt shows the borders of Ukraine in white. A slogan at the top of the back reads, "Glory to Ukraine!" and inside the shirt is a slogan that declares, "Glory to the heroes!"
Both phrases are used in Ukraine as an official military greeting.
Kremlin spokesperson Dmitry Peskov said Ukraine's choice of uniform was the prerogative of the tournament organisers.
Asked whether the Ukrainian kit could fuel trouble if Ukraine and Russia play each other in the tournament's knockout stage, Peskov said: "Sport is sport, and we need to be above the incitement of hatred between Russians and Ukrainians."
Dmitry Svishchev, a Russian parliamentarian, was quoted by news agency RIA as saying the design was "a political provocation." He said showing a map of Ukraine "which includes a Russian territory is illegal."
Russian foreign ministry spokeswoman Maria Zakharova said on social media that the slogans on the shirts were nationalistic and "Glory to Ukraine! Glory to the heroes!" echoed a German Nazi rallying cry.
The U.S. Embassy in Kyiv said it liked the new kit and wrote on Twitter: "Love the new look. Glory to Ukraine! #CrimeaisUkraine."
"I really like our team's new uniform," Ukrainian Foreign Minister Dmytro Kuleba wrote on Twitter. "I can tell those who are fussing because they can't stand our internationally recognized borders or our official state greeting: We will not allow our national symbols to be insulted!"
Relations between Moscow and Kyiv deteriorated sharply after the annexation of Crimea and the start of a Russian-backed separatist rebellion in eastern Ukraine in 2014.