Up to 13,000 Ukrainian soldiers na im don die since di start of Russia invasion, one senior official tok.
Mykhailo Podolyak, an adviser to Ukrainian President Volodymyr Zelensky, say between 10,000 and 13,000 sojas don die.
E dey rare for Ukraine to give figures for casualties, and di kontri military neva confam oga Podolyak comment.
For June e say between 100 and 200 Ukrainian sojas dey die daily.
Last month, di most senior US general, Mark Milley, say around 100,000 Russian and 100,000 Ukrainian sojas na im dem kill or wunjure since di start of di war.
For one video address on Wednesday, EU Commission head Ursula Von der Leyen say upto 100,000 Ukrainian sojas don die so far.
However toktok person for di EU Commission later clarify say di oga comment na mistake, and di figure she dey refer to na for pipo wey don die an wunjure.
Both Ukraine and Russia dey lose sojas
Speaking to Ukrainian TV Channel 24, oga Podolyak say Kyiv dey “openly tok about di number of di killed”.
“We get official evaluations by di General Staff, official evaluations by di commander-in-chief [Mr Zelensky], and dem range from 10,000 to 12,500-13,000 killed,” e tok.
E add say di number of civilians wey die fit dey “high”.
BBC News bin identify about 3,600 civilian deaths as of mid-June. Di figure fit don increase by now.
Podolyak also suggest say up to 100,000 Russian sojas don die since di invasion start 24 February, and say anoda 100,000 to 150,000 don wound or dey miss or even no fit come back to war.
Di BBC Russian Service don already confam say at least 9,311 Russian sojas from all ranks don die since di invasion on 24 February while di true death toll fit be more dan 18,600.
For anoda development, di Ukrainian military say Russia dey use dummy nuclear-capable missiles to consume Ukraine air defences.
Russia dey use rockets dem design for nuclear use without explosive warheads, Ukrainian military sabi pesin tok.
E suggest say e fit be becos di kontri don us so many of dia oda missiles in massive strikes on Ukrainian infrastructure.