EU leaders stressed on Tuesday "the inherent right of Ukraine to choose its own destiny", just three days before US President Donald Trump was due to meet his Russian counterpart Vladimir Putin.
"We, the Leaders of the European Union, welcome the efforts of President Trump towards ending Russia-Ukraine war and achieving a just and lasting peace and security for Ukraine," a statement said.
"A just and lasting peace that brings stability and security must respect international law, including the principles of independence, sovereignty, territorial integrity and that international borders must not be changed by force."
Ukrainian President Volodymyr Zelenskyy and European leaders are scheduled to meet with Trump on Wednesday.
Trump has been vague about his expectations for the meeting with Putin on Friday, describing it as a "feel-out meeting" to gauge the Russian leader's ideas for ending the war in Ukraine.
Zelenskyy has ruled out ceding territory seized by force. Trump — who publicly berated Zelenskyy at a White House meeting in February — said he was a "little bothered" by Zelenskyy’s stance and insisted land swaps would need to take place.
"There'll be some swapping, there'll be some changes in land," he said.
But Trump said he would also tell Putin that "you've got to end this war".
Alaska summit
Trump was also critical of Zelenskyy, noting that Ukraine’s leader had been in power for the duration of the war and said “nothing happened” during that time. He contrasted that with Putin, who has wielded power unchallenged in Russia for decades.
It’s unclear whether the Europeans were unsettled by Trump’s assertion that he would be travelling to Russia on Friday to meet Putin.
The summit is taking place in the US state of Alaska, which was colonised by Russia in the 18th century until Czar Alexander II sold it to the US in a land deal in 1867.
European countries fear that Putin will set his sights on one of them next if he wins in Ukraine.
