Most of the soldiers were killed in action in the eastern Donetsk region of Ukraine, mostly around the city of Avdiivka that Russian forces captured in February after a long and gruelling battle, Ukraine's Coordination Headquarters for the Treatment of Prisoners of War said in a statement.
Law enforcement agencies and forensic experts will identify the victims, who will then be handed over to family members for burial, it said.
No information has been provided about the return of any killed Russian soldiers.
In the war being waged by Russia against Ukraine for more than two and a half years, negotiations on the return of the dead or the exchange of prisoners are among the last remaining threads of dialogue between the hostile sides.
The war is believed to have killed tens of thousands of soldiers on each side although there are no official or independently collated figures.
Ukrainian President Volodymyr Zelenskiy this week disclosed parts of his so-called "victory plan" aimed at compelling Russia to end the war through negotiations.
That proposal is being considered by Ukraine's allies.
A key element would be a formal invitation into the NATO military alliance, which Ukraine's backers have been reluctant to consider until after the war ends.
Russian President Vladimir Putin said on Friday that his country was prepared to enter talks.
President Volodymyr Zelenskiy says his comments were not suggesting plans to build a nuclear weapon. (AP PHOTO)
He welcomed peace proposals previously tabled by China and Brazil, saying they could "serve as a good basis for a search for peace".
Those proposals have failed to convince Ukraine.
Speaking during a meeting with media leaders from the BRICS bloc of developing countries, Putin ruled out any concessions regarding the status of the four Ukrainian regions that Russia annexed in September 2022, saying that "those are our territories".
That would be unacceptable for Ukraine.
US President Joe Biden met Friday in Berlin with some European leaders and said that Ukraine's allies must keep up their support for the country.
The fighting has continued unabated while world leaders debate their next steps.
Russia launched 135 Shahed drones, as well as some other unidentified drones, at various parts of Ukraine on Thursday night, the Ukrainian air force said in what was one of the biggest single drone barrages of the war.
Most of the drones were intercepted, the air force said.
There was no official word on casualties or damage.
Putin also said on Friday Russia would not let Ukraine get nuclear weapons after Zelenskiy commented that since Ukraine had given up its Soviet-era nuclear arms, it must join NATO.
Putin said any move by Ukraine to get nuclear weapons could not be concealed and would draw an appropriate Russian response.
"Russia will not allow this to happen, no matter what," he told reporters.
Zelenskiy said on Thursday he had told US presidential candidate Donald Trump that Ukraine needed either nuclear weapons or NATO membership for its security - but as it gave up nuclear weapons after the break-up of the Soviet Union, joining NATO was the only way it could deter Russia.
Zelenskiy later clarified that he had never said Ukraine was preparing to build a nuclear weapon.
"We don't do nuclear weapons. Please, don't move these messages," he said.
Ukraine inherited nuclear weapons after the break-up of the Soviet Union but voluntarily relinquished them in the 1990s in return for guarantees of its territorial integrity, a deal it says officials in Moscow reneged on by invading its land.
with Reuters and DPA