Russia's defence minister has claimed the country's forces have taken control of the last major Ukrainian-held city in Luhansk province – taking Moscow closer to its stated goal of seizing all of Ukraine's Donbas region.
Sergei Shoigu told President Vladimir Putin that Russia's troops, together with members of a local separatist militia, "have established full control over the city of Lysychansk", Russian news agencies reported.
Ukrainian fighters have spent weeks trying to defend Lysychansk and to keep it from falling to Russia, as neighbouring Sievierodonetsk did a week ago.
A presidential adviser predicted late on Saturday that the city's fate could be determined within days.
Ukrainian officials did not immediately provide an update on its status.
Earlier on Sunday, Luhansk's governor said Russian forces were strengthening their positions in a gruelling fight to capture the last stronghold of resistance in the province.
Serhiy Haidai said on the Telegram messaging app: "The occupiers threw all their forces on Lysychansk. They attacked the city with incomprehensibly cruel tactics.
"They suffer significant losses, but stubbornly advance. They are gaining a foothold in the city."
A river separates Lysychansk from Sievierodonetsk.
Oleksiy Arestovych, an adviser to Ukrainian President Volodymyr Zelensky, said during an online interview late on Saturday that Russian forces had managed for the first time to cross the river from the north, creating a "threatening" situation.
He said they had not reached the centre of the city, but the course of the fighting indicated that the battle for Lysychansk would be decided by Monday.
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Luhansk and neighbouring Donetsk are the two provinces that make up the Donbas, where Russia has focused its offensive since pulling back from northern Ukraine and the capital, Kyiv, in the spring.
Pro-Russia separatists have held portions of both eastern provinces since 2014, and Moscow recognises all of Luhansk and Donetsk as sovereign republics.