Officials from Ukraine and the United States have held talks aimed at creating “reliable security guarantees” for Kyiv as part of a Washington-backed peace plan to end Russia’s war.

US Secretary of State Marco Rubio, who met with a Ukrainian delegation led by the head of Kyiv’s National Security and Defence Council, Rustem Umerov, said the discussions on Sunday were “productive” but that there is “more work to be done”.

“This is delicate. It’s complicated,” he said.

The talks took place in the US state of Florida, and included Witkoff and US President Donald Trump’s son-in-law, Jared Kushner. Witkoff leaves on Monday for Moscow, where he is expected to meet Russian counterparts for talks this week.

“We continue to be realistic about how difficult this is, but optimistic, particularly given the fact that as we’ve made progress, I think there is a shared vision here that this is not just about ending the war,” Rubio told reporters after the talks concluded.

“It is about securing Ukraine’s future, a future that we hope will be more prosperous than it’s ever been.”

He added that there were “a lot of moving parts” in the discussions, and “obviously, there’s another party involved [Russia] here that will have to be a part of the equation”.

Rubio said the US has been in touch “in varying degrees” with the Russians and has “a pretty good understanding of their views as well”.

The talks came a week after Rubio and Ukrainian negotiators met in Geneva, Switzerland, to revise Trump’s peace plan, which was initially criticised as a Russian wish list.

Umerov, writing on  X ahead of the meeting, said Ukraine had clear directives and priorities for the talks – “safeguarding Ukrainian interests, ensuring substantive dialogue, and advancing on the basis of the progress achieved in Geneva”. He added that negotiators want to “secure real peace for Ukraine and reliable, long-term security guarantees”.

After the meeting, he declared it productive.

“We discussed all the important matters that are important for Ukraine, for Ukrainian people, and [the] US was super supportive,” Umerov said.

The sit-down set the stage for Witkoff’s planned meeting with Russian President Vladimir Putin, which Trump earlier signalled would take place this week.

Putin said the US draft, which has not yet been published, could serve as a “basis for future agreements”, adding that his talks with Witkoff should focus on the Russian-occupied Donbas and Crimea regions.

‘Important days’

The negotiations come at a sensitive moment for Ukraine as it continues to push back against Russian forces, which invaded in 2022, with Ukrainian President Volodymyr Zelenskyy reeling from a corruption scandal that led to the resignation of his chief of staff, Andriy Yermak, this week.

It was Yermak who sat down with Rubio in Geneva last week to make amendments to Trump’s original 28-point plan, which initially envisioned Ukraine ceding its entire eastern region of the Donbas to Russia, limiting the size of its military, and giving up on joining NATO.

The US pared back the original draft to 19 points following criticism from Kyiv and Europe, but the current contents remain unclear.

“Ukraine’s got some difficult little problems,” Trump told reporters on board Air Force One, referring to the corruption probe that forced Yermak out.

“But I think that there’s a good chance we can make a deal,” he said.

Zelenskyy wrote on X that the US is “demonstrating a constructive approach”.

“In the coming days, it is feasible to flesh out the steps to determine how to bring the war to a dignified end,” he said.

On Sunday, the Ukrainian president said he spoke with NATO chief Mark Rutte, and noted, “These are important days and much can change.”

French President Emmanuel Macron, meanwhile, will host Zelenskyy for talks in Paris on Monday, the French presidency announced.

‘Fatigue with the war’

Theresa Fallon, the director of the Brussels-based Centre for Russia Europe Asia Studies, told Al Jazeera that Ukraine needs strong European and US support to secure a favourable deal.

“There is a real attitude of fatigue with the war. It’s winter. Its cold. The Russians have been pounding various cities in Ukraine. So, they are suffering, and they would like to see a peaceful, but one with dignity, end to this conflict,” Fallon said from the Italian city of Milan.

The talks needed hard-headed negotiators, she said, stressing that it was Putin who started the conflict and “should not be rewarded for beginning a war and all of the atrocities that were committed by Russian soldiers there”.

Ukraine, however, faces difficult days, Fallon said.

“We don’t have much support from the Europeans. The Trump administration has made it kind of clear that they don’t want to help Ukraine so much. They are willing to sell weapons to the Europeans who will pass it on to Ukraine. There’s really not a whole lot of support,” she said.

“So, I think that it’s a really hard haul for the Ukrainians, and they will have to hopefully come up with more support from the Trump administration for peace.”

On the battlefield, meanwhile, Russian forces claimed more advances, while also launching attacks on Ukraine’s capital and the region for two nights in a row.

A drone attack on the outskirts of Kyiv on Sunday killed one person and wounded 11, the regional governor said. Russian attacks overnight on Saturday, meanwhile, killed six people and wounded dozens of others across Ukraine, and cut power to 400,000 households in Kyiv.

A Ukrainian security source said on Sunday that Kyiv was responsible for attacks on two oil tankers in the Black Sea that it believed were covertly transporting sanctioned Russian oil.

One of Russia’s largest oil terminals also halted operations on Saturday following a drone attack.

The Caspian Pipeline Consortium (CPC), a group that includes US oil majors Chevron and ExxonMobil, and which owns the terminal, called the strike a “terrorist attack”.

Ukraine, which did not comment on the incident, regularly attacks Russian energy facilities in a bid to sap the country’s war chest.