Poland, steeped in bad memories of the 1939 invasion and decades of Soviet dominance after World War II, is a firm backer of Ukraine’s defense against Russia. But a flare-up over their own bloody history is threatening Polish-Ukrainian ties at a crucial time -- and could have wide repercussions.

Lieutenant General Kyrylo Budanov, Head of the Office of the President of Ukraine, believes the escalation in Ukrainian-Polish relations will peak this week, linked to Poland's…

Despite deep divisions over World War II history, both leaders stressed that countering Russia remains their shared strategic priority.

Poland, steeped in bad memories of the 1939 invasion and decades of Soviet dominance after World War II, is a firm backer of Ukraine’s defense against Russia. But a flare-up over…

Polish Prime Minister Donald Tusk said he hopes Ukrainians will rethink their approach to the Volyn tragedy and urged people in Poland to avoid inflaming emotions. [The Volyn…

As Poland observes a day of remembrance for the victims of a Ukrainian nationalist military unit, there are increasing signs that it could cut off its neighbor from military aid,…