Ukrainian President Volodymyr Zelensky has warned of Moscow's ambition to control more than just Ukraine, as Russia outlined a shift in military focus.
In his nightly video address, Mr Zelensky warned: "The Russian invasion of Ukraine was assumed to be just the beginning; further, they want to grab other countries."
Meanwhile, senior Russian military official Rustam Minnekayev publicly stated new war aims that appeared to be wider than what the Kremlin has stated in recent weeks.
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He said Russia's forces aim to take full control of not just eastern Ukraine but southern Ukraine too, opening a route to the nation of Moldova – where Russia backs the breakaway region of Transnistria.
Swathes of refugees have fled Ukraine for Moldova, as the West continues to provide aid and weapons to Kyiv.
In Ukraine itself, fierce Ukrainian counter-attacks have slowed Russian troops' offensive in the eastern Donbas region as they attempt to seize Ukraine's industrial heartland, officials have said.
Russia continues to fight for full control of the eastern Donetsk and Luhansk regions that make up the Donbas as it seeks to secure "a land route between these territories and the occupied Crimea", Ukraine's military said.
This includes an attempt to wipe out the last pocket of Ukrainian resistance in the besieged port city of Mariupol, from which Russia has pulled out military units from to bolster its broader offensive – leaving other troops to keep the remaining Ukrainian personnel in the city pinned in the Azovstal steelworks, their last remaining stronghold.
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The capture of Mariupol would deprive the Ukrainians of a vital port and complete a land corridor between Russia and the Crimean Peninsula, which it seized from Ukraine in 2014.
The UK Ministry of Defence said despite their increased activity, "Russian forces have made no major gains in the last 24 hours as Ukrainian counter-attacks continue to hinder the efforts".
Russia still has not established air or sea control due to Ukrainian resistance, and despite President Vladimir Putin’s declaration of victory in Mariupol, "heavy fighting continues to take place, frustrating Russian attempts to capture the city, thus further slowing their desired progress in the Donbas", the Ministry of Defence said.
The Kremlin has thrown more than 100,000 troops and mercenaries from Syria and Libya into the fighting in Ukraine and is deploying more forces in the country every day, said Oleksiy Danilov, secretary of Ukraine's National Security and Defence Council.
"We have a difficult situation, but our army is defending our state," he said.