The ceremony was held to coincide with the one-year anniversary of the liberation of Bucha, near the Ukrainian capital Kyiv, where many civilians were killed in the invasion by Russian forces, and President Zelensky reiterated his determination for victory, saying, "We cannot forget what happened in Bucha."

The ceremony was attended by President Zelensky as well as the leaders of Slovakia, Slovenia, Croatia and Moldova, where the Ukrainian flag was hoisted and commended soldiers and others who contributed to the defeat of the Russian army.

In Bucha, the bodies of more than 400 civilians were found after the withdrawal of temporarily occupied Russian troops, and Ukrainian prosecutors and the International Criminal Court are investigating suspected war crimes committed by Russian forces.

"After seeing what happened on the streets of Bucha, the world knew Russia's wrongdoings and what Russia was going to do in Ukraine, and we cannot afford to forget them," Zelensky said, adding, "The Ukrainian people have stopped Russia from destroying everything that is valuable to man. We will definitely win this battle."

Later, President Zelensky, who met in Kyiv with the leaders of the four countries, said that the events in Bucha had turned the world's attention to Ukraine and led to support, and that "we will do our best to get support from as many countries as possible, including those far away." Citing China, which held a summit meeting with Russia in March, as an example, he expressed his intention to seek cooperation.