GENEVA - US and Ukrainian representatives said on Sunday that their talks in Geneva on the 28-point plan to end the Russia-Ukraine conflict had "made progress," but details are unsettled as differences need to be narrowed down.

Following a meeting between the Ukrainian delegation and national security advisers from Britain, France, and Germany, the Ukrainian side held bilateral talks with the US representatives later in the day.

In the evening, US Secretary of State Marco Rubio and Andriy Yermak, head of the Ukrainian Presidential Office, briefed reporters and issued separate statements.

Rubio said the talks were the "most productive and meaningful" since the process began, noting that the delegations had worked through key points one by one and made "good progress." He said the teams were now reviewing suggestions raised during the meeting and making efforts to narrow down some remaining differences.

He added that both the US and Ukrainian sides were moving closer to a text they could agree on, although the final outcome would still require approval from the two presidents.

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Yermak described the talk with US delegations as "very productive," confirming that "very good progress" was made toward achieving a "just and lasting peace." He said both sides would continue working through proposals in the coming days and would also engage European partners as the process moves forward.

Yermak emphasized that final decisions will be made by Ukrainian President Volodymyr Zelensky and US President Donald Trump.

Both sides refused to take questions from reporters, explaining that their teams were still working on updates and preparations regarding several issues.

Although they told reporters to wait for updates later in the evening, only Rubio returned to the press two and a half hours later.

He said he was not prepared to provide any details on the specific issues under negotiation.

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Rubio reiterated that the day's negotiations had been "productive," adding that he remained "very optimistic" about reaching an agreement within a "very reasonable period of time very soon." However, he also noted that "There's no agreement yet … (some) require higher-level decisions and consultation." He added that the differences include semantics or language, and there are still issues "need more time to work through."

"The items that remain open are not insurmountable," he emphasized. He added that some contents involve equities or the role of the European Union or of the North Atlantic Treaty Organization, requiring further discussion with the European partners.

The Ukrainian delegation did not return for a second briefing.

Following the talks, Zelensky said on social media that it was essential to ensure that "the steps to end the war are effective, and that everything is doable."