The Ukrainian president said reiterated his call on the EU partners to agree on a firm date for Ukraine to join the bloc, saying that would provide an important guarantee of the country's future security as Kyiv negotiates with Moscow to end the war.
A new round of US-brokered peace talks between Ukraine and Russia, scheduled for this week, has not been cancelled following the weekend strikes on Iran by the US and Israel, Zelenskiy has said.
But Kyiv is considering a new location for the talks, which had been due to take place on March 5 and 6 in Abu Dhabi, with Turkey or Switzerland possibilities.
We are ready, but not all leaders of the European Union are... I mean, not everyone is ready to give Ukraine this opportunity," Zelenskiy told reporters in a WhatsApp media chat.
Ukraine became a formal EU candidate country in the early days after Russia's invasion in February 2022.
But so far, Kyiv's progress through the existing EU process has been held up by Hungary, which has blocked the unanimous approval required to open formally each of the six so-called accession "clusters" of issues to be resolved.
Hungarian Prime Minister Viktor Orban, who has maintained the bloc's closest ties with Russia and is facing key elections in April, has also derailed the latest EU aid package to Ukraine, worth 90 billion euros over this year and next.
Orban has accused Ukraine of stopping Russian oil supplies to Hungary via the Soviet-era Druzhba pipeline, which crosses Ukraine. Ukraine says the pipeline was damaged by a Russian drone attack.
EU officials have said that Ukraine, with a mixed record on transparency, corruption, and the rule of law, may need many years of reforms to meet the EU's entry criteria.
Zelenskiy repeated on Monday that Ukraine would be technically ready for EU accession by next year.
Kyiv sees membership in the bloc as key to its post-war future. A reference to Ukraine joining the EU at a specifically defined date is included in drafts of a 20-point peace plan that was agreed between Ukraine and the United States and is under negotiation with Russia.
On those talks the president said: "Due to the ongoing hostilities, we cannot confirm that the meeting will take place in Abu Dhabi but, nevertheless, no-one has cancelled the meeting."
Kremlin spokesman Dmitry Peskov said on Monday that it was in Russia's interests to continue peace talks with Ukraine and that Moscow's preference was still to reach a diplomatic settlement to end the four-year war.
Hostilities in the Middle East had so far no impact on weapons supplies to Ukraine from its allies, Zelenskiy said: "But, of course, we understand that a long war – if it is to be long – and the intensity of the fighting will affect the amount of air defence equipment we receive."