Ukrainian forces in Luhansk may have to retreat to avoid being captured, the region’s governor has warned.

Russian troops have entered Sievierodonetsk, the largest Donbas city that is still in Ukrainian control.

The southern Donbas region has been at the centre of the conflict after Vladimir Putin’s troops joined Russian-backed separatists who have been fighting there since 2014.

The region’s governor Serhiy Gaidai said: “The Russians will not be able to capture Luhansk region in the coming days as analysts have predicted.”

Speaking to Sky News, he added: “We will have enough strength and resources to defend ourselves.

“However it is possible that in order not to be surrounded we will have to retreat.”

Russian-backed fighters said on Saturday that they had taken control of Lyman, a rail hub west of Sievierodonetsk.

However, Ukraine said its forces were blocking Russian efforts to reach Sloviansk, to the southwest.

The UK’s Ministry of Defence said in its latest intelligence update that Russian forces “had likely captured most of the town of Lyman, in the north of Donetsk Oblast, in what is likely a preliminary operation for the next stage of Russia’s Donbas offensive.”

The statement said: “Lyman is strategically important because it is the site of a major railway junction, and also gives access to important rail and road bridges over the Siverskyy Donets River.

“If Russia did succeed in taking over these areas, it would highly likely be seen by the Kremlin as a substantive political achievement and be portrayed to the Russian people as justifying the invasion.”

But Ukrainian president Volodymyr Zelensky refused to give in to Russian pressure on Donbas, saying in a video address: “If the occupiers think that Lyman and Sievierodonetsk will be theirs, they are wrong.

“Donbas will be Ukrainian.”

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