Ukraine's president said on Sunday that he discussed an upcoming NATO summit in Lithuania's capital with his Polish counterpart.
Volodymyr Zelenskyy said on Twitter that he and Andrzej Duda met in the northwestern Ukrainian city of Lutsk, where they "had a brief but very substantive discussion" on the summit in Vilnius.
"We agreed to work together to get the best possible result for Ukraine," Zelenskyy added.
Separately, Duda said he met with Zelenskyy in Lutsk "to give a testimony of friendship in the face of a difficult history" and to hold final consultations before the NATO summit.
"Effective support for Ukraine in its pursuit of membership in the (NATO) Alliance is very important for Poland," Duda wrote on Twitter.
The two presidents made a surprise visit to the city of Lutsk in northwestern Ukraine and attended a prayer service commemorating the victims of the Volhynia massacres, during which 100,000 Poles were killed by Ukrainian nationalist extremists in 1943-1945.
"Together, we honor all the innocent victims of Volyn (Massacre). Memory unites us! Together we are stronger!" Zelenskyy said on Telegram.
Historians estimate that 100,000 Polish nationals were killed in the massacre, including 40,000-60,000 in Volhynia, 20,000-40,000 in Eastern Galicia, and at least 4,000 in the territory of modern-day Poland.
About 10,000-12,000 Ukrainians were also murdered during Polish retaliatory operations by the spring of 1945, according to Poland's National Remembrance Institute.
