A historical feud threatens a key wartime alliance for Ukraine

UkraineA historical feud threatens a key wartime alliance for UkraineWorld War II mass killings are putting a new strain on relations between Ukraine and Poland, one of its most ardent backers against Russia.Polish archaeologists work in April last year at the exhumation site of mass killings in the village of Puzniki, Ukraine. PVladyslav Musiienko / AFP via Getty ImagesShareAdd NBC News to GoogleJune 27, 2026, 5:30 AM EDTBy Yuliya TalmazanPoland says it’s taking a stand over a bloody massacre. Ukraine says it’s a needless affront to a nation fighting for survival. Limited time: Save 25% on NBC News subscriptionGet exclusive reporting, live Q&As and ad-free reading.Kyiv and its allies may be feeling pretty good about the present state of the war with Russia, but an intense historical feud has reignited, threatening relations between Ukraine and one of its most ardent backers.The dispute between Warsaw and Kyiv comes just as Europe has re-engaged the United States in pressuring Moscow to end the war, with officials on the continent warning the neighbors’ tensions would play into the hands of President Vladimir Putin.President Karol Nawrocki’s move to strip Ukrainian President Volodymyr Zelenskyy of Poland’s top honor earlier this month elevated the spat to a full-blown crisis, with Zelenskyy skipping a key wartime conference in Poland that began Thursday.It all centers on the Ukrainian Insurgent Army (UPA), which Poland accuses of mass killings during World War II. Some in Ukraine view the UPA as nationalist heroes for their resistance to Soviet and Nazi forces. But Zelenskyy’s decision to name a military unit after the UPA drew fury from Warsaw, which had already shown signs of war fatigue over the influx of refugees and economic drain of supporting Ukraine’s fight. Ceremonies at the grave of the unknown soldier of the Ukrainian Insurgent Army in Lviv have inflamed tensions with neighboring Poland. Les Kasyanov / Global Images Ukraine via Getty Images fileThe ti...