Ukrainian President Volodymyr Zelenskiy raised his fist as he branded Russia a "terrorist state" following a missile attack in front of a civilian public administration building in Kharkiv.
Zelenskiy said the attack on the city's central square was an "open, undisguised terror attack" - saying "No one will forgive. No one will forget."
It come as Zelenskiy submitted formal requests to join the EU,
Speaking via video link to an emergency session of the European Parliament, he urged members to "prove that you are with us" in Ukraine's war with Russia, a day after asking to join the bloc.
European Union lawmakers, many wearing #standwithUkraine T-shirts bearing the Ukrainian flag, others with blue-and-yellow scarves or ribbons, gave Zelenskiy a standing ovation.
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"We are fighting to be equal members of Europe," Zelenskiy said in Ukrainian in a speech translated into English by an interpreter who spoke through tears.
"Do prove that you are with us. Do prove that you will not let us go. Do prove that you are indeed Europeans, and then life will win over death and light will win over darkness," he said.
"The EU will be much stronger with us." Zelenskiy has remained in Kyiv to rally his people against the invasion. As he spoke on Tuesday, a Russian armoured column was bearing down on Ukraine's capital.
The presidents of eight central and eastern European nations on Monday published an open letter calling for Ukraine to be granted immediate EU candidate status and for the start of formal membership talks.
Charles Michel, the chairman of EU leaders, told the EU Parliament after Zelenskiy's speech that the bloc would have to seriously look at Ukraine's "legitimate" request to join.
But he added: "It is going to be difficult, we know there are different views in Europe (about further enlargement)."
According to a draft text they will vote on later on Tuesday, EU lawmakers are expected to brand Russia a "rogue state" and urge member states to agree even tougher sanctions.
The EU has taken unprecedented steps, including financing weapons deliveries to Ukraine, after President Vladimir Putin launched war on Russia's neighbour last week.