Russia’s attempt to seize the town of Vuhledar has lost momentum after being slowed by Ukrainian anti-armour mines, British officials believe.
The UK’s Ministry of Defence said on Thursday that a feud between Russian officials and the mercenary Wagner group could be prolonging the battle.
Ukraine’s President Volodymyr Zelenskyy said overnight that Russia’s assault on the country was “approaching the point where it can break”.
European leaders were meanwhile warned that public support for Ukraine could weaken if it does not keep up its battlefield successes.
The struggle for Vuhledar, a Ukrainian-held town in eastern Donetsk, has become a key flashpoint as Russia looks for gains on the front line.
Despite “repeated, extremely costly failed attacks”, Russia’s assaults on the town have “almost certainly slowed”, the British ministry said in a daily intelligence update.
One reason has been Ukraine’s use of remote anti-armour mines, it said, of which more than 10,000 rounds have been provided by the US military.
The tactic involves firing an artillery shell to scatter small explosives in a radius of up to 17km.
Some of the mines have landed behind Russian lines and caused problems for retreating tanks, according to the UK officials.
They said a “realistic possibility” was that the Russian military was maintaining its pursuit of Vuhledar to avoid being outpaced by Wagner Group gains in nearby Bakhmut.
Wagner boss Yevgeny Prigozhin has gone public with his criticism of Russia’s leadership as casualties mount in Ukraine.
Mr Zelenskyy said overnight that Ukrainian regiments were “delivering results” in Bakhmut and the wider Donetsk region.
America's top general Mark Milley said Moscow's troops were making small advances near Bakhmut but at “very heavy costs”.
The Russian-installed leader of Donetsk has conceded there is no sign of Ukraine withdrawing troops from Bakhmut, pro-Kremlin media said on Thursday.
Ukraine’s battlefield successes have galvanised support in Europe where pro-Kyiv sentiment remains broadly strong, analysts at the European Council on Foreign Relations said in a report published on Thursday.
A poll of nine European countries found that 38 per cent believed Ukraine should push to regain all its territory even if the war drags on, while only 29 per cent said the war must end as soon as possible.
However, the two main Republican contenders to challenge Joe Biden for the US presidency in 2024 have questioned Washington’s support for Ukraine in recent days.
“One year into the war, Europe is more united than ever”, the think tank’s director Mark Leonard said.
“But the next year could put real pressure on this — if Ukraine suffer setbacks on the battlefield, the costs of refugees rise, or Washington pulls back.”