Ukraine said it had begun "hard" talks on a ceasefire, immediate withdrawal of troops and security guarantees with Russia on Monday, despite the fatal shelling of a residential building in Kyiv.

Both sides suggested at the weekend some results could be in sight after earlier rounds have primarily focused on ceasefires to get aid to towns and cities under siege by Russian forces and evacuate civilians; those truces have frequently failed. 

Firefighters tackled the remains of a blaze at the damaged apartment block in the capital, where a stunned young resident described the chaos of the previous night in a city targeted by the Russian advance but so far largely spared bombardment.

Officials said at least one person died in the shelling and a second person was killed by falling debris after a missile strike on another part of the Ukrainian capital. 

"The staircase was not there anymore, everything was on fire," Maksim Korovii told Reuters, describing how he and his mother had first hid inside their dust and smoke-filled apartment, thinking Russian forces were breaking down the door.

"We didn’t know what to do. So we ran out to the balcony. We managed to put on whatever clothes we had at hand and made our way from balcony to balcony and in the end we climbed down by the next building's entrance," he said.

Russia denies targeting civilians, saying it is conducting a "special operation" to demilitarise and "denazify" Ukraine. Ukraine and Western allies call this a baseless pretext for a war of choice.

Russia's defence ministry said at least 20 people had been killed and 28 wounded when what it said was a Ukrainian missile with a cluster charge exploded in the capital of the eastern Donetsk region, without providing evidence.

Pro-Russian separatists who control the region said earlier a child was among those hit in what it called a war crime. Ukrainian officials denied the reports, which Reuters was unable to independently verify.

Ukrainian negotiator Mykhailo Podolyak, who on Sunday said Russia was beginning to talk "constructively", wrote ahead of the talks: "Negotiations. 4th round. On peace, ceasefire, immediate withdrawal of troops & security guarantees."

He later said discussions had started but were hard, because the political systems of Russia and Ukraine were too different.

Podolyak said he believed Russia "still has a delusion that 19 days of violence against (Ukrainian) peaceful cities is the right strategy."

Russia has accused Ukraine of using civilians as human shields, an allegation Kyiv has firmly denied.

Reuters

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