MOSCOW — Moscow is hoping to achieve "some progress" at talks in Saudi Arabia on Monday, a Russian negotiator told state media before the United States meets Ukrainian and Russian delegations separately in a bid to halt the three-year conflict.

US envoy Keith Kellogg described the effort as "shuttle diplomacy" between hotel rooms.

Ukraine will meet the US mediators first, with President Volodymyr Zelensky saying he was "prepared" for Sunday's talks.

A separate meeting between US and Russian officials in the Gulf country is scheduled for Monday.

The US hopes to reach a broad cease-fire within weeks, targeting a truce agreement by April 20, Bloomberg News reported on Sunday, citing people familiar with the planning.

Despite the flurry of diplomacy, a breakthrough has so far proved elusive.

"We hope to achieve at least some progress," Russian Senator Grigory Karasin, who will lead the Russian delegation, told the Zvezda TV channel on Saturday, without specifying on what issue.

Karasin said he and his fellow negotiator, FSB adviser Sergey Beseda, would take a "combative and constructive" mood into the talks.

"We are going with the mood to fight for the solution of at least one issue," Karasin said.

A senior Ukrainian official told AFP a day earlier that Kyiv hopes to secure agreement "at least" on a partial cease-fire covering attacks on energy infrastructure and at sea. Kyiv is sending its defense minister to the negotiations.

In Washington, a source briefed on the planning of the meetings in Saudi Arabia said the US side would be led by Andrew Peek of the National Security Council and Michael Anton of the State Department.

On Sunday, the Kremlin downplayed expectations for a rapid resolution to the conflict.

"We are only at the beginning of this path," Kremlin spokesman Dmitry Peskov told Russian state TV, adding there were many outstanding "questions" and "nuances" over how a potential cease-fire might be implemented.

"There are difficult negotiations ahead," Peskov said in the interview, published on social media.

Zelensky said on Saturday he had met top military commanders in Ukraine's northeast to discuss the frontline and meetings with US officials.

He was shown on X with commanders in Ukraine's second-largest city Kharkiv, a frequent target of Russian attacks.

He said he discussed frontline sectors in the east as well as in western Russia's Kursk region.

Earlier on Saturday, Zelensky visited the eastern Donetsk region, where he met commanders of drone units near the strategic city of Pokrovsk.

The governor of the Donetsk region said on Saturday that three people had been killed in Russian shelling of Pokrovsk.

Russia's Defense Ministry said it had "destroyed and intercepted" 59 Ukrainian drones overnight, mostly over the regions of Rostov and Astrakhan.

Meanwhile, US Middle East envoy Steve Witkoff said on Friday that Zelensky has largely conceded that Ukraine will not be able to join NATO.

In an interview with US journalist Tucker Carlson, Witkoff said Zelensky and Andriy Yermak, head of the Ukrainian president's office, have "largely conceded that they are not going to be a member of NATO".

Agencies via Xinhua