Russia has lost up to 40% of the units it dispatched into Ukraine since February 24, according to the Ukrainian military’s general staff.
He stated in the daily broadcast that the troops were either fully decimated or had lost their combat capability, but he did not provide specific numbers.
According to the German news agency Dpa, the information could not be independently verified.
The situation in the area surrounding besieged Mariupol remained critical.
The Russian army was attempting a blockade of the city from the western and eastern fringes of the port city, but was suffering “significant losses,” according to the bulletin.
Ukrainian authorities said some 20,000 people from Mariupol, on the Sea of Azov, managed to get to safety on Tuesday.
About 30,000 civilians nationwide were able to leave threatened areas on Tuesday, but a column with relief supplies for Mariupol is still being blocked by Russian soldiers, Ukrainian President Volodymyr Zelensky said.
In the Odessa region, Russian ships were shelling the Ukrainian coast but there was no attempt to land, Interior Ministry adviser Anton Herashchenko said.
So far, reports Reuters, Moscow has not captured any of Ukraine’s 10 biggest cities following its incursion that began on Feb. 24, the largest assault on a European state since 1945.
Ukrainian said Moscow may be coming to terms with its failure to impose a new government by force and running out of fresh troops
Ukrainian and Russian representatives are set to resume their negotiations on Wednesday.
Zelensky said demands are starting to get more realistic, while warning it would still take a while before Ukraine can be satisfied with talks.
Meanwhile the prime ministers of Poland, the Czech Republic and Slovenia assured Zelensky of their solidarity and support during a visit to Kiev.
They travelled to Kiev by train in a gesture of support for Ukraine.