Talks between Ukraine and the US aimed at reaching a peace deal with Russia are continuing in Berlin for a second day.
Zelensky and his chief negotiator Rustem Umerov met US envoy Steve Witkoff and Donald Trump's son-in-law Jared Kushner for five hours on Sunday, joined by German Chancellor Friedrich Merz.
A lot of progress was made, a US readout said. The same team resumed talks on Monday morning.
Ahead of the start of the meeting, Volodymyr Zelensky signalled he would give up ambitions to join NATO in exchange for security guarantees.
Recognising that some partners from the US and Europe did not support Ukraine's bid for NATO membership, Zelensky said he was instead seeking strong security guarantees modelled on NATO's Article 5 clause of mutual protection.
Witkoff has travelled to Moscow to hold talks with Vladimir Putin on several occasions, but Sunday's meeting at the chancellery in Berlin was the first time he met Zelensky. NATO Supreme Allied Commander Europe General Alexus Grynkewich was also present at the talks.
Several European leaders as well as European Commission President Ursula von der Leyen are expected to join further talks with the Ukrainian and US delegations on Monday evening.
At the core of the discussions in Berlin is the 20-point peace plan proposal presented to the US by Ukraine last week to counter an initial American plan which was seen as heavily favouring Russia.
Details haven't been shared, but last week Zelensky said the points should be seen as a foundation on which to build provisions for the reconstruction of Ukraine and security guarantees.
For Russia, Kyiv's membership of NATO is a red line, and Moscow has repeatedly demanded that any ambitions for Ukraine to join the alliance are shelved forever.
Before the talks began, Zelensky addressed the issue of sovereignty over the eastern region of the Donbas, which Russia mostly occupies. While he was open to freezing the conflict along the current front line, he insisted his troops would not withdraw unless Russian forces did the same.
The Kremlin has noted it expects the US to provide the concept discussed on Monday.
The ongoing negotiations take place amid a dire situation for Ukraine as it experiences power outages due to ongoing attacks on energy facilities. EU countries are also discussing a significant financial support plan that hinges on frozen Russian assets.
