Volodymyr Zelensky says 31,000 Ukrainian soldiers have been k__led during Russia’s full-scale invasion.
The Ukrainian president said he would not give the number of wounded as that would help Russian military planning.
Typically, Ukrainian officials do not make public the numbers of servicepeople k__led in the war.
It comes after the defence minister said half of all Western aid for Ukraine has been delayed, costing lives and territory.
Mr Zelensky said on Sunday that he was providing an updated death toll in response to the inflated figures that Russia has quoted.
“31,000 Ukrainian soldiers have died in this war. Not 300,000 or 150,000, or whatever Putin and his lying circle are saying. But each of these losses is a great loss for us.”
Speaking about the wider losses in the war, Mr Zelensky said tens of thousands of civilians had died in the areas of Ukraine occupied by Russia but the true number was unknown.
“I don’t know how many of them died, how many were k__led, how many were m____red, t_____ed, how many were deported.”
It is rare for Ukraine to provide a military death toll, and other estimates suggest a much higher number.
US officials in August put the number of Ukrainian soldiers k__led at 70,000 and as many as 120,000 injured.
According to Mr Zelensky, 180,000 Russian soldiers have been k__led and tens of thousands more injured.
BBC Russian, in a joint project with the Mediazona website, recently reported that it had established the names of more than 45,000 Russian servicepeople who had died. But it estimates the total number to be greater than that.
In February, the UK’s defence ministry estimated that 350,000 Russian troops had been k__led or injure
