Ukraine and Russia have accused each other of violating a three-day ceasefire which was declared by Vladimir Putin last week and came into effect on Thursday.
Russia breached the truce, to which Kyiv hasn't signed up, 734 times since it started, Ukraine's foreign minister Andrii Sybiha said, adding Moscow had carried out 63 "assault operations".
Those figures, he said, were for the period between midnight and midday local time.
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Kyiv claimed the violations took place in the northern region of Sumy and the east.
One person died and two were wounded when Russian forces dropped guided air bombs on residential areas near the border in the northeast Sumy region, the regional prosecutor's office said.
But just minutes after Mr Sybiha's accusations, Moscow responded with its own claims against Kyiv.
Quoting Russia's defence ministry, state media reported Ukraine broke the ceasefire 488 times.
Russia's defence ministry also claimed on Thursday that Ukraine had tried twice to push through the border in the Kursk region where Ukraine launched a surprise incursion last summer, Russian news agency Interfax reported.
Ukraine has, in recent months, lost ground in Kursk. Russia has claimed Ukrainian troops have been pushed out completely.
Russian President Vladimir Putin said the three-day ceasefire, lasting from 8-10 May, was to mark the 80th anniversary of the victory of the Soviet Union and its allies over Nazi Germany in World War Two.
Mr Putin is due to host Chinese President Xi Jinping and a number of other leaders at a military parade on Moscow's Red Square on Friday.
Ukraine never signed up to the Kremlin's 72-hour truce, saying it was a ruse by Mr Putin to make it look like he wants peace.
But Ukrainian President Volodymyr Zelenskyy has said he is ready to observe a 30-day ceasefire, something the US proposed in March.
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Meanwhile, President Xi has arrived at the Kremlin for talks with Mr Putin, who described his guest as a "dear friend".
Mr Putin has said he appreciates the chance to communicate directly with him and will visit China "with pleasure".
Their cooperation is "aimed at the wellbeing of our people", and not against anyone else, Mr Putin added.
Mr Xi described Mr Putin as an "old friend" and said he is happy to be in Russia.
(c) Sky News 2025: Ukraine and Russia accuse each other of breaching Moscow-declared ceasefire