GENEVA 

The US and Ukraine reported significant progress on Sunday after what both sides described as the most productive discussions to date in ongoing negotiations for a Russia-Ukraine peace deal, with US Secretary of State Marco Rubio touting the talks.

Rubio told a press briefing at the US Mission in Geneva that the first session of the meeting marked "probably the most productive and meaningful meeting so far in this entire process," adding that the discussions were built on extensive input from all parties.

"We were able to go through some of the items now, point by point. And I think we’ve made good progress," he said.

Rubio added that delegations had broken off to refine proposals aimed at narrowing remaining gaps. "We're working through making some changes, some adjustments, in the hopes of furthering narrowing the differences and getting closer to something that both Ukraine and obviously the United States are very comfortable with," he said.

"Obviously, this will ultimately have to be signed off of our presidents, although I feel very comfortable about that happening,” he said, adding that the US also has “substantial insights” into Russia’s priorities.

Ukraine’s presidential chief of staff Andriy Yermak, for his part, confirmed the positive momentum.

"I want to confirm that we have (a) very productive first session with distinguished American delegation. We have very good progress, and we are moving forward to the just and lasting peace Ukrainian people deserve and want this peace more than any more anyone in this planet," he said.

Yermak thanked the US for their commitment, adding that work would continue in the coming days and with European partners.

Rubio concluded by saying the delegations would return later with updates. "Let us work on more answers for you … We will come back later tonight," he said.

- 28-point plan sparks concern

The 28-point US plan to end the over 3 1/2-year-old war is on the table in Geneva, where representatives of Washington, Kyiv, and European capitals met to discuss details.

US President Donald Trump said Saturday that the US-drafted plan would not be his "final offer" as the proposal has sparked concerns in Kyiv and among its allies.

The draft appears to require Ukraine to surrender additional territory to Russia, limit the size of its military, and formally abandon its bid to join NATO. Trump has given his Ukrainian counterpart until Thursday to respond.

Zelenskyy said he faces a tough choice, namely the "loss of our dignity or the risk of losing a key partner."

On Saturday, the leaders of nine European countries plus Japan, Canada, and top EU officials expressed concern over the plan's proposed limitations on Ukraine's armed forces, warning that they "would leave Ukraine vulnerable to future attack."