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Up to 100 soldiers are being killed every day in frontline fighting against Russian troops, with hundreds more being wounded in "brutal and difficult" battles, Ukraine's defence minister has said.
Fighting raged on the streets of Severodonetsk again on Thursday, with Russian forces destroying “everything that can be used for defence”, said Luhansk's regional governor Sergiy Gaiday.
The city has come under fire for weeks and Ukraine’s President Volodymyr Zelenskyy has called it the “epicentre of the confrontation in Donbas”.
Defence Minister Oleksiy Reznikov said: "The situation at the front lines is difficult. Every day we have up to 100 of our soldiers killed and up to 500 wounded. The Kremlin continues to press by sheer mass, stumbles, faces strong resistance and suffers huge casualties."
Petro Kusyk, commander of Ukraine's Svoboda National Guard Battalion, said Ukrainians were drawing the Russians into street fighting in Severodonetsk to neutralise Moscow's artillery advantage.
The Russian military is advancing in parts of the Donbas region, the key battlefield of the war in Ukraine, the UK Ministry of Defence said on Thursday.
The push, to the south of Izium, is believed to be an attempt to regain momentum and pile pressure on Ukrainian fighters defending Severodonetsk, the MoD said in a daily briefing.
“Fighting continues in the Severodonetsk pocket but, in the last 48 hours, Russia’s Eastern Group of Forces [EGF] have also likely increased their efforts to advance to the south of Izium,” the MoD said.
“Russia’s progress on the Izium axis had remained stalled since April, after Ukrainian forces made good use of the terrain to slow Russia’s advance.
“Russia has likely attempted to reconstitute EGF after they suffered very heavy casualties in the failed advance on Kyiv, but its units likely remain understrength.
“Russia likely seeks to regain momentum in this area in order to put further pressure on Severodonetsk, and to give it the option of advancing deeper into the Donetsk Oblast.”
British Prime Minister Boris Johnson said any attempts to impose a "bad peace" on Ukraine, through granting territorial concessions to Russia, would be "morally repugnant".
"Never mind that abandoning the Ukrainians would be morally repugnant, since they are the victims and they have an absolute right to defend a free and independent country," he said.
"We are simply not in a position to tell them what to do."
Mr Johnson did not identify anyone pushing for a peace deal. But last week, French President Emmanuel Macron drew criticism for saying the West "should not humiliate Russia" and instead provide Mr Putin with a diplomatic "exit ramp".
Russian troops have been trying to seize Severodonetsk, a city that had a population of more than 100,000 before the invasion, while facing Ukrainian counter-attacks.
About 15,000 people remain and Russian troops control a large area of the city, local authorities said.
“It is a very brutal fight, a very difficult one,” Mr Zelenskyy said in his daily video address.
“It is probably one of the most difficult during the whole war. In many respects, the fate of our Donbas is being decided there.”
Mr Gaiday said Severodonetsk was “largely” under Russian control after fierce fighting, while its twin city of Lysychansk was suffering heavy damage.
“The industrial zone is still ours, there are no Russians there. The fighting is only going on in the streets inside the city," he said.
“The Russians are shooting at everything. They are destroying all the houses in Severodonetsk, with tanks, artillery.
“They are shooting at the industrial zone too, but the fighting is going on, our guys are resisting in the streets.”
The city has become the focus of Russia's offensive as it seeks to seize the eastern flank of Ukraine, after being repelled from the capital Kyiv and other parts of the country.
Severodonetsk and Lysychansk, which are separated by a river, were the last areas under Ukrainian control in the region.
