In a statement, the European leaders said a "just and lasting peace" must uphold Ukraine's independence, sovereignty and territorial integrity, stressing that borders "must not be changed by force," Xinhua reported.
"The path to peace in Ukraine cannot be decided without Ukraine," they said. "Meaningful negotiations can only take place in the context of a ceasefire or reduction of hostilities."
The bloc reiterated its support for Ukraine's political, economic, humanitarian, military and diplomatic needs, and pledged to continue to uphold and impose restrictive measures against Russia.
The leaders also reaffirmed their support for Ukraine to join the EU.
Hungary did not sign the statement. Prime Minister Viktor Orban wrote on X that Hungary would not back a statement setting conditions for a meeting to which EU leaders were not invited.
US President Donald Trump and Russian President Vladimir Putin are scheduled to meet in Alaska on Friday to discuss a possible Russia-Ukraine ceasefire and ways to improve bilateral ties.
Ukrainian President Volodymyr Zelensky said on Saturday that Ukraine would not cede territory to Russia after Trump suggested there could be some "swapping of territories" to end the war.