The International Committee of the Red Cross (ICRC) is working with the United Nations in an ongoing operation to move people out of Mariupol and the besieged Azovstal steel plant, the ICRC said in a statement.
"The 1st group of about 100 people is already heading to the controlled area," Volodymyr Zelensky added.
Ukrainian officials have been giving more details on the evacuation of civilians who had been trapped at the Azovstal steep plant.
David Arakhamia, an advisor to President Zelensky, said: "Today is the third day of a special operation we call "Azovstal evacuation." Since the beginning of the war, since the beginning of the blockade of Azovstal, we have managed to withdraw more than 100 civilians - small children, women and the elderly."
Iryna Vereshchuk, deputy prime minister, said on Ukrainian television: "Sorry, we were silent. We really wanted everything to work out. Our silence was in order for people to come out alive and unharmed. More than 100 people have been evacuated, and the evacuation continues. All this happened thanks to the control of the President of Ukraine Zelensky, Antonio Guterres, and the International Committee of the Red Cross, for which we are very, very grateful."