Ukrainians have repelled multiple attempts by the Russians to cross a strategically significant river in the Donbas, inflicting heavy losses in the process, according to local officials and British intelligence.
Ukrainian forces have also driven Russia from the second-largest city of Kharkiv in their fastest advance since Kremlin troops pulled away from Kyiv and the north-east over a month ago to focus their offensive on the Donbas.
The city, which had been under fierce bombardment, has been quiet for at least two weeks and Ukraine now controls territory stretching to the Siverskyi Donets river, around 40 km (25 miles) to the east.
Serhiy Haidai, the governor of the Luhansk region, said Russian forces had been repulsed three times as they tried to cross the river, losing armour and bridging equipment.
“We have eliminated Russian speedboats and helicopters which they used to cover their attempts,” the governor added, while aerial photography showed destroyed pontoon bridges and armour by the riverbanks.
Earlier on Friday, British defence intelligence said Russia had lost “significant armoured manoeuvre elements” from a battalion tactical group – a formation with about 800 personnel at full strength – from the failed efforts.
Russian attempts to gain territory in the Donbas are increasingly focused on Severodonetsk, the easternmost town held by Ukrainian forces – and the Russian forces were trying to cross the river in an attempt to cut off the town.
Ukraine’s defence ministry tweeted pictures of a smashed pontoon bridge and destroyed armoured vehicles in Bilohorivka on Wednesday, describing them as showing victims of “artillerymen of the 17th tank brigade”.
The British assessment appeared to verify that, and quantify the level of loss – effectively the equipment strength of one battalion of up to 90 Russian units operating in and near Ukraine.
Another open source analyst estimated 73 Russian pieces of equipment, including tanks and armoured vehicles, were destroyed, relying on aerial photography of the aftermath of the battle.
“Conducting river crossings in a contested environment is a highly risky manoeuvre and speaks to the pressure the Russian commanders are under to make progress in their operations in eastern Ukraine,” the British Ministry of Defence said on Friday morning.
Russian forces in the Donbas have made incremental progress on the north side of the Siverskyi Donets, and are assessed to be in control of Rubizhne to the north-west of Severodonetsk by the Institute for the Study of War.
Winning control of the town has taken Russian forces “two to three weeks”, western officials added, representing an incremental pace of advance by Moscow. “Russian doctrine in this kind of conflict would have its forces moving at some 40km a day,” an official added.
Nevertheless, despite suggestions by US intelligence officials earlier this week that the conflict had largely ground to a standstill, other observers still believe Severodonetsk is at risk, in what is set to be a crucial battle in the struggle for control of the Donbas.
“They will likely launch a ground offensive on or around Severodonetsk in the coming days,” the Institute for the Study of War said, but added it was “unclear if Russian forces can encircle, let alone capture” Severodonetsk, as the impetus in the Russian effort in the Donbas region appeared generally to have faded.
A Russian offensive further west, south of Izium, had stalled for several weeks and was appearing to lose momentum, the institute added. Izium is one of the few places where Russia had managed to cross the Siverskyi Donets, but its forces have been unable to advance from there.
Western officials say they believe Russia will form a defensive line behind the river, partly to protect its supply lines to forces trying to make headway further south. “This a staged and gradual withdrawal from Kharkiv,” one said, which would allow the Russian invaders to “replenish and circulate their forces”.
Elsewhere, Ukraine claimed it had damaged a Russian navy logistics ship near Snake Island in the Black Sea – which is still being fought over.
Satellite imagery provided by Maxar, a private US-based company, showed the aftermath of what it said were probable missile attacks on a Russian Serna-class landing craft near the island, close to Ukraine’s sea border with Romania.
Renewed fighting around Snake Island in recent days may become a battle for control of the western Black Sea coast. Russia wants to maintain air defences on the island to protect its maritime operations – while for Ukraine the struggle has become symbolic, western officials added.
Olaf Scholz, the German chancellor, spoke to the Russian president, Vladimir Putin, for the first time since the start of the war, urging Moscow to reach a ceasefire agreement and raising concern about international food supplies that have been disrupted by the fighting, according to Berlin’s account of the 75-minute call.
Meanwhile, Ukraine’s president, Volodymyr Zelenskiy, warned the French leader, Emmanuel Macron, was trying “in vain” to have a constructive dialogue with Putin, in an interview with Italian television – suggesting there was little appetite in Kyiv for a cessation of fighting at the moment.
“We must not look for a way out for Russia,” Zelenskiy said – although the Élysée Palace said Macron had “never discussed anything with Vladimir Putin without the agreement of President Zelenskiy”.