President Volodymyr Zelensky said Ukraine forces are continuing to retake more villages with the Russians retreating and a US officer has claimed that winning back Crimea is now a "distinct possibility".
While Vladimir Putin has announced the annexation of four regions of Ukraine, on the ground his army has been struggling and now Zelensky has said that three villages - Novovoskresenske, Novohryhorivka and Petropavlivka - to the north east of the city of Kherson have been "liberated".
Ukraine has said it will never accept an illegal seizure by force after Putin signed a law on Wednesday to incorporate Donetsk, Luhansk, Kherson and Zaporizhzhia following referendums that have been widely called in the West as "shams".
It is Europe's biggest annexation attempt since World War Two, with Putin saying he wants to ensure his country's security and protect Russian-speakers in Ukraine.
But with the Russian army being forced to retreat further on a daily basis recently, a US officer has reportedly said that "the recapture of Crimea by Ukraine is now a distinct possibility and can no longer be discounted."
Speaking to the Telegraph the official continued: " It is clear that Russia no longer has the ability or willpower to defend key positions, and if the Ukrainians succeed in their goal of recapturing Kherson, then there is a very real possibility that it will ultimately be able to recapture Crimea."
Zelensky said in a nightly address that he and his senior military officials met on Wednesday to discuss recovering all lands occupied by Russia.
Switching to Russian, Zelensky addressed pro-Moscow forces, telling them they had already lost.
"Ukrainians know what they are fighting for. And more and more citizens of Russia are realizing that they must die simply because one person does not want to end the war," he said in a reference to Putin.
Moscow's map of Ukraine appears to show shrinking areas it controls. A map of "new regions" published by state news agency RIA included the full territory of the Ukrainian provinces, but some parts were shaded and labelled as being under Ukrainian military control.
"They will be with Russia forever," Kremlin spokesman Dmitry Peskov said of the new regions, adding that settlements recaptured by Ukraine in recent days "will be returned".
Ukrainian forces have recaptured thousands of square miles of territory since the start of September, including dozens of settlements in just the past few days.
Thousands of Russian troops retreated after the front line crumbled, first in the north east, and, since the start of this week, also in the south.
Putin celebrated the annexations in a ceremony in the Kremlin followed by a concert on Red Square last week, only hours before Ukrainian forces captured Lyman, Russia's main bastion in the northern part of Donetsk.
In one of his first moves to assert his rule over the four annexed provinces, Putin ordered the Russian state to seize control of Europe's biggest nuclear power station, still run by Ukrainian engineers despite being captured early in the war by Russian troops.
The UN nuclear watchdog, the IAEA, said it had learned of plans to restart one reactor at the plant, where all six reactors have been shut down for weeks.
The Zaporizhzhia power station is located right on the front line, on a Russian-controlled bank of a giant reservoir with Ukrainian forces on the opposite bank, and both sides have warned of the danger of a nuclear disaster from fighting near it.
In recent days, Russia detained the Ukrainian manager in charge of the plant. He has since been released but will not return to work. The head of Ukraine's state nuclear energy company Energoatom, Petro Kotin, said he was now taking charge of the plant and urged workers not to sign any documents with its Russian occupiers.
