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A fourth round of talks between Moscow and Kyiv got under way on Monday, a senior Ukrainian negotiator said, amid mutual claims of shelling and civilian deaths earlier in the day.
Kyiv's lead negotiator and presidential aide Mikhailo Podolyak posted a picture on Twitter of videoconference talks.
He described the negotiations as “hard”, saying that the two sides were outlining their “specific positions”, AFP reported.
Three rounds of talks between the two sides in Belarus, most recently last Monday, focused mainly on humanitarian issues.
Ukrainian President Volodymyr Zelenskyy said the countries' delegations have been speaking daily by video and a clear aim of his negotiators was to “do everything” to arrange for him to meet Russian President Vladimir Putin.
Amid the diplomatic efforts, fighting has continued to rage.
The Antonov aircraft plant in Kyiv has been shelled by Russian forces, the Kyiv city administration said on Monday.
Two people were killed in the strike and a nearby residential building was also targeted by Russian shelling, city officials said.
A barrage of Russian missiles hit an Ukrainian base just 25 kilometres from the Polish border that has previously hosted Nato military instructors, killing 35 people and wounding 134, a Ukrainian official said on Sunday.
Foreign mercenaries
Russia's defence ministry said as many as 180 “foreign mercenaries” and a large number of foreign weapons were destroyed.
Russia has asked China for military equipment, sparking concern in the White House that Beijing may undermine Western efforts to help Ukrainian defenders, US officials said earlier.
Huge, unexploded bomb removed from Ukraine home
US National Security Adviser Jake Sullivan, who is set to meet China's top diplomat Yang Jiechi in Rome on Monday, warned Beijing it would “absolutely” face consequences if it helped Moscow evade sanctions, Reuters reported.
But when asked about Russia's request for military aid, Liu Pengyu, the spokesman for China's embassy in Washington, said, “I've never heard of that.”
China found the current situation in Ukraine “disconcerting”, he said, adding, “We support and encourage all efforts that are conducive to a peaceful settlement of the crisis.”
Meanwhile, air raid sirens sounded before dawn in many cities and regions of Ukraine, including Kyiv, Lviv, Odessa, Ivano-Frankivsk and Cherkasy.
In Kyiv, at least one person was killed and three were wounded when a shell hit a residential building, state television said.
Authorities said they were stockpiling two weeks' worth of food for the two million people who have not yet fled from Russian forces attempting to encircle the capital.
A US journalist was shot and killed by Russian forces in the town of Irpin, north-west of Kyiv, and another was wounded, the regional police chief said.
Britain's defence ministry said Russian naval forces had established a distant blockade of Ukraine's Black Sea coast, isolating the country from international maritime trade.
In eastern Ukraine, Russian troops were trying to surround Ukrainian forces, as they advanced from the port of Mariupol in the south and the second city Kharkiv in the north, it added.
The city council in Mariupol said 2,187 residents had been killed since the start of the invasion.
Moscow denies aiming at civilians and blames Ukraine for failed attempts to relocate civilians from encircled cities.
Ukraine and its Western allies have strongly rejected the accusations.
Slow progress
Meanwhile, one of Mr Putin's closest allies said Russia's military operation in Ukraine had not all gone as quickly as the Kremlin had wanted, Reuters reported.
National Guard chief Viktor Zolotov, speaking at a church service led by Orthodox Patriarch Kirill on Sunday, blamed the slower-than-expected progress on what he said were far-right Ukrainian forces hiding behind civilians, an accusation repeatedly made by officials in Russia.
His comments appeared at odds with an assessment on Friday by Russia's Defence Minister Sergei Shoigu, who told Putin that “everything is going according to plan".
“I would like to say that yes, not everything is going as fast as we would like,” Mr Zolotov, once in charge of Putin's personal security, said in comments posted on the National Guard's website.
