People gather during the distribution of humanitarian aid in Mariupol, April 5, 2022.(Photo: Xinhua)

Osnat Lubrani, UN resident coordinator and humanitarian coordinator in Ukraine, said Thursday that she is heading to Zaporizhzhia city in southern Ukraine to prepare for evacuation from Mariupol.

"The (UN) Secretary General Antonio Guterres has arrived in Ukraine to meet (Ukrainian) President (Volodymyr) Zelensky. At his request, I am going to Zaporizhzhia to prepare for hopeful evacuation from Mariupol," tweeted Lubrani.

The UN is fully mobilized to help save Ukrainian lives and to assist those in need, Lubrani said.

Guterres arrived in Ukraine on Wednesday to talk with Zelensky, after visiting Moscow on Tuesday.

Mariupol, a key Azov Sea port city in eastern Ukraine, saw one of the worst violence in the Russia-Ukraine conflict.