Ukraine and Poland have agreed to work on joint border controls as well as a shared railway company to relieve the movement of people and grow Ukraine's export potential.
Meanwhile, Ukrainian President Volodymyr Zelenskyy has said that only diplomacy will end the war with Russia, as his top officials rule out a ceasefire or ceding any territory.
Russia continues its push into the Donbas with heavy strikes on numerous cities in eastern Ukraine.
Poland's president became the first foreign leader to give a speech in person to the Ukrainian parliament since Russia's Feb. 24 invasion.