Ukrainian President Volodymyr Zelensky said the Ukrainian army had made major, rapid advances against Russian forces and liberated dozens of cities in the south and east of the country from occupation.

"The Ukrainian army is advancing in a fairly fast and powerful way in the south of the country in the context of the current defense operation," Zelensky said in a video address.

According to him, only this week, after the Russian "pseudo-referendum, dozens of settlements in the regions of Kherson, Kharkiv, Luhansk and Donetsk" were liberated.

On September 30, Russian President Vladimir Putin signed documents formalizing Russia's attempt to annex the Ukrainian regions of Donetsk, Luhansk, Kherson and Zaporizhia, parts of which were occupied by Russian forces. Earlier, Moscow organized a referendum in those four regions that was rejected by the international community.