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Russia scored an early point in the “battle for the Donbas” by capturing the city of Kreminna hours after the major offensive was launched, amid a warning from the Kremlin to western nations that arming Ukraine risked prolonging the war.
Sergei Shoigu, the Russian defence minister, said forces were “methodically carrying out” orders to “liberate” the two breakaway regions of Donetsk and Luhansk.
Hours after Ukrainian President Volodymyr Zelenskyy announced the beginning of the offensive in an overnight video address, the regional governor of Luhansk said Kreminna had fallen. The city, 660 kilometres east of Kyiv had a pre-war population of more than 18,000.
“Kreminna is under the control of the 'Orcs' [Russians]. They have entered the city,” Sergiy Gaiday, the governor of the Luhansk region, told a briefing. “Our defenders had to withdraw. They have entrenched themselves in new positions and continue to fight the Russian army.”
He did not specify exactly when the Russians wrested control of the city from Ukrainian forces but said they had attacked “from all sides".
“It is impossible to calculate the number of dead among the civilian population. We have official statistics — about 200 dead — but in reality there are many more,” he said, without saying what period the estimated death toll covered.
The Donbas region has been a focal point of Russia’s campaign to destabilise Ukraine since 2014, when the Kremlin began using proxies to set up separatist “people's republics” in Luhansk and Donetsk.
Mr Shoigu warned Ukraine’s allies against sending further weapons supplies to the former Soviet nation before a virtual meeting between the leaders of the G7, Nato and the EU. The videoconference called by US President Joe Biden scheduled for Tuesday afternoon is expected to focus on sending heavy weapons to try to boost Kyiv’s chances of defeating the Russians.
“The plan to liberate the Donetsk and Luhansk People's Republics is being methodically carried out,” Mr Shoigu was quoted by the RIA news agency as saying, at a meeting of defence officials.
Western countries have given Ukraine military equipment worth billions of dollars, with the US alone offering aid worth more than $2.5 billion (£1.9 billion).
“The United States and western countries it controls are doing everything to drag out the special military operation as much as possible,” Mr Shoigu said. “The increasing volume of foreign arms supplies clearly demonstrates their intentions to provoke the Kyiv regime to fight to the last Ukrainian standing.”
Moscow refers to the war in Ukraine as a “special military operation” designed to demilitarise the neighbouring country and remove what it calls dangerous nationalists.
Kyiv and its western allies reject that as a false pretext for an unprovoked attack that has forced almost 5 million people to flee abroad and internally displaced about 7 million.
On Tuesday, day 55 of the invasion, French finance minister Bruno Le Maire said a ban on Russian oil imports was needed “more than ever”. There has been heated debate within the energy-dependent bloc about the merits of restricting flows.
Mr Le Maire told Europe 1 radio that France hoped to convince EU partners “in coming weeks” to stop oil imports from Russia and said such a move should be prioritised over a ban on gas.
However, a full and immediate ban on Russian oil could push the price of crude to $185 a barrel, JP Morgan said in a report.
Mr Le Maire acknowledged that not all of the EU’s 27 member states seemed to be in favour of an oil ban.
“We are trying to convince our European partners to stop importing oil from Russia. What has been the primary source of currency for Vladimir Putin for several years? It is not gas. It is oil,” he said.
European leaders in March distanced themselves from US efforts to ban Russian oil imports. Days later President Biden issued an executive order banning the import of oil, gas and other energy products from Russia.
The UK on Tuesday moved to further hamper the Russian economy, following several rounds of sanctions against individuals, banks and businesses.
Its tax authority, HM Revenue and Customs, announced plans to revoke the Moscow Stock Exchange’s status as a recognised stock exchange in response to the invasion.
The move would remove some tax relief for investors.
“Revoking Moscow Stock Exchange’s recognised status sends a clear message — there is no case for new investments in Russia,” said Lucy Frazer, the UK's Financial Secretary to the Treasury.
A senior national security official gave UK Prime Minister Boris Johnson and his cabinet an update on the situation in Ukraine, a spokesman for Mr Johnson said on Tuesday.
The offensive in the Donbas was likely to be prolonged and bloody, the spokesman said.
“The next phase of the war was likely to be an attritional conflict that could last several months,” he said.
“Russia would aim to exploit its troop number advantage, but Ukraine had already shown that this was unlikely to be decisive on its own.
“There were some signs that Russia had not learnt lessons from previous setbacks in northern Ukraine, and there was evidence of troops being committed to the fight in a piecemeal fashion.”
Russia announced a string of retaliatory measures against European nations on Tuesday, banning 15 diplomats from its territory. The announcement came after several European nations expelled Russia’s representatives.
The Russian foreign ministry declared 15 diplomats from the Netherlands “persona non grata”, giving them two weeks to leave, and gave the same deadline to Belgium's embassy staff.
Brussels in March expelled 21 Russian envoys and Moscow said at the time it would retaliate by following the “principle of reciprocity”. However, it did not make clear how many Belgian staff it was expelling.
The Russian government also gave four Austrian diplomats until Sunday to leave Russia. Moscow's announcement came a week after Austrian Chancellor Karl Nehammer became the first European leader to visit Mr Putin since he ordered his troops into Ukraine.