Poland’s nationalist president Karol Nawrocki announced on Friday he was stripping Ukraine’s Volodymyr Zelensky of the country’s top award, escalating a row between the neighbours and allies over World War II massacres. Relations between Warsaw and Kyiv have been tense for days over Zelensky’s naming of a Ukrainian army unit after a WWII nationalist insurgent army that took part in massacres against Poles. Nawrocki’s decision landed days before Poland is due to host the annual Ukraine Recovery...