Questions are also swirling around the future of US support once Donald Trump assumes the presidency in January, with fears he could force Kyiv to make painful concessions in pursuit of a quick peace deal.
Zelenskyy said his country needed to be in a “strong position” before any talks with the Kremlin, calling for “steps forward with Nato” and a “good number” of long-distance weapons to defend itself.
“Only when we have all these items and we are strong; after that, we have to make the very important ... agenda of meeting with one or another of the killers,” the Ukrainian leader said, adding that the EU and Nato should be involved in any negotiations.
Costa said the European Union would give Ukraine its “unwavering” support.
“We have stood with you since the very first day of this war of aggression, and you can count on us to continue to stand with you,” he told Zelenskyy.
The European Union’s new leadership team is keen to show it remains firm on backing Kyiv at a perilous moment for Ukraine nearly three years into its fight against Russia’s invasion.
Russian President Vladimir Putin threatened this week to strike government buildings in Kyiv with his new Oreshnik missile, after the US gave Ukraine approval to fire long-range ATACMS missiles into Russia for the first time.
A Russian drone dropped explosives on a bus in the southern Kherson region on Sunday, killing three people, authorities said, while the Russian army claimed to have captured two new front-line villages in the east.
Zelenskyy on Friday appeared to begin staking out his position ahead of any potential peace talks.
He called on Nato to offer guaranteed protections to parts of Ukraine controlled by Kyiv in order to “stop the hot stage of the war”, and implied he would then be willing to wait to regain other territory seized by Russia.
“If we will have a frozen conflict without any strong position for Ukraine, Putin will come back in two, three or five years,” Zelenskyy said on Sunday.
Kallas told journalists on the journey into Ukraine for Kyiv, “the strongest security guarantee is Nato membership”.
“We need to definitely discuss this – if Ukraine decides to draw the line somewhere, then how can we secure peace so that Putin doesn’t go any further?” she said.
But diplomats at Nato say there appears little prospect of the alliance granting Ukraine membership soon given opposition from a raft of members cautious of getting dragged into war with Russia.
Zelenskyy insisted Kyiv was not “delusional” about its prospects with Nato and admitted there was deep reluctance from incumbent US President Joe Biden, along with leaders in countries such as Hungary.
Kallas said the EU “shouldn’t really rule out anything” in terms of the question of sending European troops to help enforce any ceasefire.
“We should have this strategic ambiguity around this,” she said.
Trump has cast doubt on continuing Washington’s vast aid for Ukraine and called on EU countries to do more.
Europe together has spent around $125 billion on supporting Ukraine since Russia’s 2022 invasion, while the United States alone has coughed up over $90b, according to a tracker from the Kiel Institute.
Kallas said the EU would use a “transactional language” to try to convince Trump backing Kyiv was in the interest of the US.
“Aid for Ukraine is not charity,” she said. “A victory for Russia definitely emboldens China, Iran, North Korea.”
– Agence France-Presse