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Russian troops are likely to retreat to southern and eastern strongholds in Ukraine after partially withdrawing from around Kyiv, senior Ukrainian figures said on Saturday.
Mykhailo Podolyak, a senior adviser to President Volodymyr Zelenskyy, said Ukraine needed more weapons to drive out the Russian invaders after more than five weeks of war.
But he rejected suggestions that the war would develop into a drawn-out conflict like the one in Afghanistan, after Mr Zelenskyy suggested some western countries were quietly hoping Russia would remain bogged down.
Russia’s announcement this week that it was scaling back its operations around Kyiv was met with scepticism by western leaders, amid uncertainty over whether troops were really withdrawing or merely regrouping.
But British military intelligence said on Saturday that Ukrainian forces were advancing against withdrawing Russian troops near Kyiv and had retaken several villages.
Mr Zelenskyy meanwhile said the partial Russian withdrawal was “slow, but noticeable” and said some positions had been abandoned by the Kremlin’s forces.
Ukraine claimed on Saturday that almost 18,000 Russian troops had been killed and more than 600 tanks lost during an invasion that western officials say has failed to make the progress expected.
However, Mr Zelenskyy said bombing attacks continued and that Russia was leaving mines behind in the regions evacuated by its troops. “It is still impossible to return to normal life as it was,” he said.
Mr Podolyak predicted that Russian forces would leave all regions except the south and east and “try to dig in there, set air defence, drastically reduce losses and dictate terms”.
He said Russia was hoping to control a vast stretch of territory in the south and east, where Ukraine currently holds the port of Mariupol despite weeks of fighting that have triggered a humanitarian crisis in the city.
The Red Cross said a team trying to organise an evacuation had to turn back on Friday because “conditions made it impossible to succeed”. Ukraine has accused Russia of obstructing aid convoys.
Mr Zelenskyy described the situation in Mariupol as a “humanitarian catastrophe” and said European powers had “no right to react in silence”.
Russia has said it would focus on the eastern Donbas region where it supports pro-Kremlin separatists in the self-declared republics of Donetsk and Luhansk.
“Without heavy weapons we won’t be able to drive [Russia] out,” Mr Podolyak said in the latest appeal for western countries to provide more armaments.
But “there’ll be no Afghanisation and no long conflict”, he said, after the prospect of a drawn-out war led to comparisons with the long Soviet and Nato interventions in Afghanistan.
Germany, Australia and Lithuania have all approved extra weapons transfers to Ukraine, with Berlin approving the export of PbV-501 infantry fighting vehicles.
The 56 vehicles originally belonged to communist East Germany and were sold to Sweden and then a Czech company after the end of the Cold War, but the government of the reunified Germany retains a veto over such transfers.
Lithuania’s Defence Minister Arvydas Anusauskas said the Baltic country was transferring another 10 million euros’ ($11m) worth of military support to Ukraine.
Australia announced it would send armoured Bushmaster vehicles to Ukraine after Mr Zelenskyy specifically asked for them in a speech to the country’s Parliament, the latest in a series of such addresses.
The vehicles will be flown over on Boeing C-17 Globemaster transport aircraft, said Australian Prime Minister Scott Morrison.
“We’re not just sending our prayers, we are sending our guns, we’re sending our munitions,” said Mr Morrison.
Peace talks were described as making some progress this week but the future of the disputed Donbas and Crimea remain up in the air.
Ukraine offered at the talks in Turkey to adopt a form of neutrality in which several named countries would guarantee to protect it from aggression as a substitute for a Nato membership bid which Russia wants dropped.