Ukraine, Poland leaders jointly mark WWII massacres that strained ties

Ukraine's President Volodymyr Zelenskiy and Polish President Andrzej Duda attend a church service, amid Russia's attack on Ukraine, in Lutsk, Ukraine, July 9, 2023. REUTERS/Alina Smutko

KYIV (Reuters) - The Ukrainian and Polish presidents jointly marked the anniversary on Sunday of World War Two-era massacres of Poles by Ukrainian nationalists, killings that have caused tension for generations between countries that are now close allies.

Warsaw has positioned itself as one of Kyiv's staunchest supporters since Russia invaded the country in 2022.