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 delegations from both Ukraine and Russia in a bid to halt the three-year conflict.

Moscow has rejected a joint US-Ukraine proposal for a full and unconditional 30-day ceasefire, suggesting instead halting aerial strikes on energy facilities, reports AFP. Despite that offer, both sides have continued to launch aerial attacks in the run-up to the negotiations.

A Russian strike on the southern Ukrainian city of Zaporizhzhia on Friday night killed a family of three, triggering anger among Ukrainian officials. Russia also launched drone attacks on Kyiv that hit apartment buildings and caused fires, killing at least two people, Ukraine's emergency service said early Sunday. Kyiv mayor Vitali Klitschko said Sunday a "massive attack by enemy UAVs" caused falling debris in several districts of the city, wounding seven.

US negotiators will meet separately with Ukrainian and Russian delegations in Saudi Arabia on Monday, in what US envoy Keith Kellogg described as 'shuttle diplomacy' between hotel rooms.

Despite the flurry of diplomacy and push from US President Donald Trump, 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, without specifying on what issue.

He said he and fellow negotiator, FSB advisor Sergey Beseda would take a "combative and constructive" mood into the talks. A senior Ukrainian official told AFP a day earlier that Kyiv hopes to secure agreement "at least" on a partial ceasefire covering attacks on energy, infrastructure and at sea. Kyiv is sending its defence minister to the negotiations.

"We are going with the mood to fight for the solution of at least one issue," Karasin told Zvezda, which is owned by Russia's defence ministry. He said they were leaving for Saudi Arabia on Sunday and would return on Tuesday.