“[There are] constant strikes on the Odesa region, on the cities of central Ukraine. The Donbas is completely destroyed,” he said.
“All this has not and cannot have any military explanation for Russia. This is a deliberate and criminal attempt to kill as many Ukrainians as possible. Destroy as many houses, social facilities and enterprises as possible.”
Russia has refocused its offensive on the region in the past month following an unsuccessful attempt to capture key cities in central Ukraine, including Kyiv. Mr Putin’s army has also failed so far to gain control of Kharkiv, Ukraine’s second-largest city in the northeast.
His comments came just hours before the regional governor of the Luhansk region, Serhiy Gaidai, said that Russian shelling had killed 13 civilians in the past 24 hours.
Twelve were killed in the town of Sievierodonesk, where a Russian assault has been unsuccessful, he said. The town and the city of Lysychansk are in an area where Russian troops have launched an offensive.
Mr Gaiday added: “Information about the number of dead and injured is still being determined because it is impossible to examine the territory under shelling.”
The UK Ministry of Defence (MoD) said that Russia was likely to reinforce its operations in the Donbas once they had secured the southern city of Mariupol.
As many as 1,700 soldiers are likely to have surrendered at the Azovstal steel factory in the besieged city, the MoD’s report added.
"Staunch Ukrainian resistance in Mariupol since the start of the war means Russian forces in the area must be re-equipped and refurbished before they can be redeployed effectively," the ministry wrote on Twitter.
"Russian commanders, however, are under pressure to demonstrably achieve operational objectives. That means that Russia will probably redistribute their forces swiftly without adequate preparation, which risks further force attrition."
Russia’s deputy Prime Minister Marat Khusnullin this week visited the Kherson and Zaporizhzhia regions, large swathes of which are now under Moscow’s control, and said they could become part of “our Russian family”.
Volodymyr Saldo, the Kremlin-installed head of the Kherson region, also appeared in a video on Telegram saying the occupied city of Kherson "will become a subject of the Russian Federation."