Polish Prime Minister Donald Tusk has issued a direct appeal to Ukraine for “truth” and “mutual respect” as a diplomatic row over World War II historical legacies escalates. The dispute centers on the 1943 Volhynia massacre, in which Ukrainian nationalists killed tens of thousands of ethnic Poles. Warsaw has long pressed Kyiv to acknowledge the killings as genocide and to allow the exhumation and proper burial of victims, a process that has been stalled for years.