Earlier this week, Russia said it would drastically reduce its military presence in Kyiv and Chernihiv.
The Ukrainian president's adviser, Okeksiy Arestovych, says Ukrainian troops have now retaken more than 30 cities and villages since the Russian withdrawal.
- In the northern part of the country, the intruders have left - slowly but noticeably.
In some parts they have been fired after fighting, in other parts they have abandoned their position themselves, says President Volodymyr Zelenskyj in a video released on Saturday and quoted by Reuters.
The president also accuses the Russians of having mined everything - even the dead.
But those accusations have not been met by Russia's defense minister, according to Reuters.
At the same time, there are reports from the Kremlin that one of the goals of the "military operation" was to liberate Donetsk and Luhansk and return to the borders that existed in 2014, according to Reuters.
Mass grave in Butja
After the readmission, there are reports of great devastation and many deaths - including in the suburb of Butja outside Kyiv.
An area hard hit by the fighting.
A mass grave with about 300 dead is to be found in the city on Saturday.
Pictures from the news agency Reuters show large graves filled with sand where body parts protrude.
Earlier in the day, 20 bodies were found lying on a street in the city.
"They were all shot, killed by bullets in the neck," local mayor Anatoly Fedoruk told AFP.
He says many of the victims wore white armbands to show they were unarmed.
According to the mayor, they had tried to cross a river to escape.