Russian forces have lost about 4,300 servicemen during their invasion of Ukraine, Deputy Defense Minister Hanna Malyar said on Sunday, adding however that the number was being clarified.
She also said on her Facebook page that Russian troops lost about 146 tanks, 27 aircraft and 26 helicopters.
This came as the regional governor of Kharkiv announced that his country has full control over the northeastern city.
"Control over Kharkiv is completely ours! The armed forces, the police, and the defense forces are working, and the city is being completely cleansed of the enemy," Oleh Sinegubov wrote on Telegram.
Ukrainian forces battled Russian troops on the streets of Kharkiv on Sunday as the Russian light vehicles entered Kharkiv, including the city center.
"Ukraine's armed forces are destroying the enemy. We ask civilians not to go out," said Sinegubov in earlier statements.
Videos published by Anton Herashchenko, adviser to the interior minister, and Ukraine's state information agency showed several light military vehicles moving along a street and, separately, a burning tank.
A witness in Kharkiv said Russian soldiers and armored vehicles could be seen in different parts of the city and firing could be heard.