Over the past 24 hours, with the help of humanitarian corridors, 28,893 Ukrainians were rescued from the combat areas of Sumy, Kharkiv and Donetsk regions, President of Ukraine Volodymyr Zelensky said in a video message at the night on Wednesday.

"I hope that on Wednesday the long-awaited rescue of people from the city of Izium in Kharkiv region will take place. The humanitarian corridor has been agreed," he said.

Of those rescued on Tuesday 20,000 were able to leave Mariupol, Zelensky said. So far only by own transport.

"There will be a difficult situation. We are fighting for you. I'm sorry, it's very complicated. The Ukrainian convoy with humanitarian cargo is still constantly blocked by Russian soldiers on the road to the city. But we will not give up trying to save people, save the city," the president said.