European Council head António Costa said the funding would take the form of an emergency loan backed by the EU budget and financed through joint borrowing.
Speaking after the summit, Costa said the decision "will provide Ukraine with the necessary means to defend itself and to support the Ukrainian people," adding that Kyiv would only be expected to repay the loan once Russia pays future reparations.
Costa rejected suggestions that the outcome exposed divisions within the bloc, saying the agreement showed the EU was still able to act collectively in support of Ukraine.
"We committed, and we delivered," he said, adding that work would continue on possible mechanisms to link the loan to future reparations based on frozen Russian assets.
European Commission chief Ursula von der Leyen said the decision to guarantee the loan with the EU budget was taken unanimously.
However, only 24 member states will take part in the joint borrowing, with Hungary, Slovakia and the Czech Republic opting out.
Also, EU leaders failed to agree on a plan to finance the loan using frozen Russian sovereign assets, instead deciding to raise the money on capital markets.
Von der Leyen said that while proposals to use Russian assets had been discussed, leaders ultimately opted to keep those assets immobilised rather than use them to fund the package.
She said the debate had nevertheless helped secure continued agreement among member states to maintain the freeze on Russian assets, which previously had to be renewed every six months amid resistance from some governments.
Denmark's Prime Minister Mette Frederiksen, whose country currently holds the EU presidency, warned that European governments were facing increasing domestic political pressure.
She said Russian President Vladimir Putin was counting on "war fatigue" in Europe, combined with hybrid warfare tactics designed to undermine public confidence and security.
Ukraine's President Volodymyr Zelensky expressed his gratitude for the decision, writing on X that "it truly strengthens Ukraine's resilience".
(ał/gs)
Source: PAP, Reuters