In another development, French President Emmanuel Macron said he believed it would be "useful" for Europe to re-engage with Russian President Vladimir Putin.
"I believe that it's in our interest as Europeans and Ukrainians to find the right framework to re-engage this discussion," he said, adding that Europeans should find the means to do so "in coming weeks".
EU leaders avoided "chaos and division" with their decision to provide Ukraine with a loan through borrowing cash rather than use frozen Russian assets, Belgian Prime Minister Bart De Wever said early on Friday.
"We remained united," De Wever added.
Ukraine is months from running out of cash and Zelensky said without an injection by spring Ukraine would "have to reduce production of drones".
The EU estimates Ukraine needs an extra €135 billion to stay afloat over the next two years, with the cash crunch set to start in April.
German Chancellor Friedrich Merz, who had pushed for the asset plan, said the final decision on the loan "sends a clear signal" to Putin.
Russia had warned EU leaders not to use its money, but Polish Prime Minister Donald Tusk said they had to "rise to this occasion".
The agreement offers Kyiv a desperately needed lifeline amid a flurry of diplomacy as US President Donald Trump pushes for a quick deal to end Russia's war.
US and Russian officials are due to meet in Miami this weekend for further talks on a peace plan, a White House official has told AFP news agency. It is thought Kremlin envoy Kirill Dmitriev will talk to Trump envoys Steve Witkoff and Jared Kushner in Miami.
Meanwhile, Zelensky announced Ukrainian and US delegations would hold new talks on Friday and Saturday in the United States.
He said he wanted Washington to give more details on the guarantees it could offer to protect Ukraine from another invasion.