Sviatoslav Palamar, Azov’s deputy commander, said in video message: "My command and I are on the territory of the Azovstal plant. An operation is underway. I will not give any details. I’m grateful to the whole world and to Ukraine for support. I will be seeing you!"

Read here Red Cross registered hundreds of Ukrainian soldiers leaving the Azovstal

The Ukrainian side has not given an update on the number who have left Azovstal nor on the status of negotiations for their exchange for Russian prisoners.

Ukraine said it expects to carry out an exchange of Russian prisoners of war for the severely injured soldiers.