The Ukrainian military says a soldier has been killed in shelling by pro-Russian separatists in east Ukraine, where violence this week in a long-running conflict has stirred concern about Russian military action.
The Ukrainian military said on its Facebook page it recorded 19 ceasefire violations by the separatists since the start of the day compared with 66 cases over the previous 24 hours.
Separatists opened fire on more than 20 settlements, using heavy artillery, which have been prohibited by Minsk agreements, the military said on Saturday.
Incidents of shelling across the line dividing government forces and separatists increased sharply this week, in what the Ukrainian government called a provocation.
It strongly denied suggestions by Russia that Kyiv could launch an offensive in eastern Ukraine.
The Minsk accords aim to end an eight-year-long conflict between the Ukrainian army and separatists in the east of the country.
Earlier the head of the pro-Russian separatist government in Ukraine's eastern Donetsk region ordered a full military mobilisation and and urged reservists to show up at military enlistment offices.
On Friday, separatist authorities in Donetsk and Luhansk announced a mass evacuation of women, children and the elderly to neighbouring Russia.
Shortly after the evacuation effort started, several explosions hit the rebel-controlled areas.
The separatist conflict in eastern Ukraine erupted in 2014 and has killed more than 14,000 people.
US President Joe Biden says he is now "convinced" Russian President Vladimir Putin has decided to invade Ukraine and assault the capital.
After weeks of saying the US was not sure if Putin had made the final decision, Biden said on Friday that his judgement had changed, citing American intelligence.
"As of this moment, I'm convinced he's made the decision," Biden said. "We have reason to believe that." He reiterated the assault could occur in the "coming days".
The president's comments at the White House followed a day of rising violence that included a humanitarian convoy hit by shelling and a car bombing in Donetsk.
Meanwhile, the Kremlin announced massive nuclear drills to flex its military muscle, and Putin pledged to protect Russia's national interests against what it sees as encroaching Western threats.
Biden reiterated his threat of crushing economic and diplomatic sanctions against Russia if it does invade, and pressed Putin to reconsider.
He said the US and its Western allies were more united than ever to ensure Russia pays a steep price for any invasion.
As further indication that the Russians are preparing for a major military push, a US defence official said an estimated 40 to 50 per cent of the ground forces deployed in the vicinity of the Ukrainian border have moved into attack positions closer to the border.
That shift has been under way for about a week, other officials have said, and does not necessarily mean Putin has decided to begin an invasion.
Australian Associated Press
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