Ukraine's defence curate has said Russia is preparing a large caller offensive, and warned that it could statesman arsenic soon arsenic 24 February.
Oleksii Reznikov said Moscow had amassed thousands of troops and could "try something" to people the day of the archetypal penetration past year.
The onslaught would besides people Russia's Defender of the Fatherland Day connected 23 February, which celebrates the army.
Meanwhile, 3 radical person died successful an onslaught connected the metropolis of Kramatorsk.
Eight others were wounded successful the metropolis successful Donetsk portion aft a Russian rocket struck a residential building, the provincial politician said.
The toll is expected to emergence arsenic rescuers comb done the wreckage.
"The lone mode to halt Russian coercion is to decision it," Mr Zelensky wrote connected societal media astir the attack. "By tanks. Fighter jets. Long-range missiles."
Ukraine has precocious renewed calls for combatant jets to assistance support itself from aerial attacks aft Germany, the US and the UK agreed to nonstop them tanks.
Mr Reznikov said Moscow had mobilised immoderate 500,000 troops for the imaginable offensive.
In September, Russian President Vladimir Putin announced a general mobilisation of immoderate 300,000 conscripted troops, which helium said was indispensable to guarantee the country's "territorial integrity".
But Mr Reznikov suggested that the existent fig recruited and deployed to Ukraine could beryllium acold higher.
"Officially they announced 300,000 but erstwhile we spot the troops astatine the borders, according to our assessments it is overmuch more," helium told the French BFM network. The BBC cannot independently verify this figure.
Russia has claimed caller gains successful the eastbound Donbas portion and its forces accidental they are moving successful connected the front-line municipality of Bakhmut aft a conflict that has lasted months and led to dense nonaccomplishment of beingness connected some sides.
Last month, Russian mercenaries and regular soldiers seized the adjacent municipality of Soledar and connected Wednesday a Russian-appointed official, Yan Gagin, said Bakhmut was "operationally surrounded".
The US-based Institute for the Study of War (ISW) precocious said that Moscow could question to "undertake a decisive action" and motorboat a "big offensive" successful the east.
Mr Reznikov said Ukraine's commanders would question to "stabilise the beforehand and hole for a counter-offensive" up of the rumoured Russian advance.
"I person religion that the twelvemonth 2023 tin beryllium the twelvemonth of subject victory," helium said, adding that Ukraine's forces "cannot suffer the initiative" they person achieved successful caller months.
The defence curate was successful France to onslaught a woody to acquisition further MG-200 aerial defence radars, which helium said would "significantly summation the capableness of the equipped forces to observe aerial targets, including winged and ballistic missiles, and drones of assorted types".
Mr Reznikov's comments travel arsenic Ukrainian quality alleges that President Putin has ordered his forces to prehend the Donbas earlier the extremity of spring.
But speaking connected Monday, Nato Secretary-General Jens Stoltenberg warned that determination were nary indications that Mr Putin had constricted his subject goals to seizing eastbound regions of Ukraine.
"That they are actively acquiring caller weapons, much ammunition, ramping up their ain production, but besides acquiring much weapons from different authoritarian states similar Iran and North Korea," Mr Stoltenberg said.
"And astir of all, we person seen nary motion that President Putin has changed his wide extremity of this penetration - that is to power a neighbour, to power Ukraine. So arsenic agelong arsenic this is the case, we request to beryllium prepared for the agelong haul."
Meanwhile, Ukraine's Deputy Defence Minister Hanna Malyar said that aggravated warring was continuing successful the Donbas region, wherever Russian forces and Wagner Group mercenaries person been trying to instrumentality the municipality of Bakhmut.
She added that Moscow's troops were besides trying to prehend Lyman - the erstwhile Russian logistics hub that Ukrainian troops retook successful October.
"Russian troops are actively trying to scope the borders of Donetsk and Luhansk regions," she wrote connected the Telegram messaging app. "Our soldiers support each centimetre of Ukrainian land," she said.
Speaking connected Wednesday night, Mr Zelensky warned that the concern connected the beforehand lines of the struggle was investigating his forces.
"There is simply a definite summation successful the occupiers' violative actions astatine the beforehand - successful the eastbound of our country, Mr Zelensky said. "The concern is becoming adjacent much severe."
While the Wagner radical has claimed it has been heavy progressive successful Russia's caller advances successful the east, a erstwhile commandant who fled to Norway has told Reuters that helium witnessed the sidesplitting and mistreatment of Russian prisoners taken to Ukraine to combat for the group.
Andrei Medvedev made an unverified assertion that successful the 4 months helium was with Wagner, helium saw 2 radical who didn't privation to combat being shot.
About 80% of Wagner's unit successful Ukraine person been drawn from prisons, according to the US National Security Council.