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Moscow has identified Kherson as a vital focal point for its invasion as it seeks to establish a southern land corridor that would link the mainland to the Crimean Peninsula, which it seized from Ukraine in 2014.
Kherson, which has a population of 300,000 people, became one of the first cities to become contested during the devastating conflict which has now entered its third month.
"Russia previously held an illegitimate referendum on the accession of Crimea into the Russian Federation in 2014 to retrospectively justify its seizure of the Peninsula," the UK's Ministry of Defence said on Twitter.
"Russia’s own domestic elections have been beset by allegations of vote rigging and have seen high-profile opposition blocked from running."
In a further update today, Britain said Russia's offensive has made only minor advances in the contested Donbas region due to staunch resistance from Ukrainian troops. This is particularly the case in the strategic coastal city of Mariupol, where fighting has "exhausted many Russian units and reduced their combat effectiveness."
"Without sufficient logistical and combat support enablers in place, Russia has yet to achieve a significant breakthrough," the intelligence update added.
US officials today also indicated that they believe the Kremlin is "failing" in its war aims.
Washington has pledged new aid worth $713 million for Ukraine and other countries in the region fearful of further Russian aggression.
“The strategy that we’ve put in place — massive support for Ukraine, massive pressure against Russia, solidarity with more than 30 countries engaged in these efforts — is having real results,” US Secretary of State Antony Blinken told reporters in Poland the day after meeting with Mr Zelenskyy and other Ukrainian officials.
“When it comes to Russia’s war aims, Russia is failing. Ukraine is succeeding. Russia has sought as its principal aim to totally subjugate Ukraine, to take away its sovereignty, to take away its independence. That has failed.”
Mr Zelenskyy said he was “very thankful” for the American aid and praised US President Joe Biden for his “personal support.”
Meanwhile, it was reported that a large fuel depot in a Russian town close to the border with Ukraine is on fire, the emergency situations ministry was quoted as saying by Russian news agencies today.
Social media footage showed at least two big fires, purportedly near the city of Bryansk, which serves as a logistics base for Moscow's military operation.
"A fire has been reported at the Transneft Bryansk-Druzhba fuel depot in Bryansk," around 150 kilometres (93 miles) from the Ukraine border.
It comes as Russian forces shot down two Ukrainian drones near the border overnight, a regional governor said today.
"Today at 4.15am, Russian air defence crews shot down two Ukrainian drones in the Rylsky district on the border with Ukraine", Kursk region governor Roman Starovoyt said on Telegram.
"There are no casualties, injuries or damage. The situation is completely under control."