Russia’s military operation in Ukraine will be “unsustainable” within three weeks, a defence expert has said.
Ed Arnold, a research fellow for European security at the Royal United Services Institute (RUSI) think tank, said Russia is meeting more resistance from Ukrainian troops than it expected.
He told the Reuters news agency on Monday: “At the current rate of Russian losses, which are not confirmed, but we do have indications that this operation would be unsustainable within about three weeks from the Russian perspective.”
He added: “In which case that they would have to consolidate the gains already made and look to see a way of trying to freeze the conflict on the current lines of advance while they mobilise more forces from Russia.”
While Arnold said Russia continues its advance into Ukraine, he described its progress as “slow”.
He said: “Within the north, they are still looking to fully encircle Kyiv.
“In the south, the Russian advance is continued to be slow but they're seeing a lot more successes in the south, taking Kherson and consolidating and pushing further west, and then also focusing now on Mariupol.
“However, at the moment, the Russian operation is going so badly, especially from logistics point of view that really Russia might just not have the numbers to make another conflict that is cold be hot again."
His comments came as Ukraine claimed on Monday it had retaken the city of Chuhuiv from Russian troops.
Lieutenant General Serhiy Shaptala said defending Ukrainian forces had seized Chuhuiv from Russian control, killing two high-ranking Russian commanders in the process.
Ukraine’s military, the General Staff, said on Facebook: "In the course of hostilities, the city of Chuhuiv was liberated.
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"The occupiers suffered heavy losses in personnel and equipment.”
Ukrainian and Russian negotiators are expected to sit down for a third round of peace talks on Monday.
The discussions will take place in Belarus, close to the border with Poland.
In the previous set of talks last Thursday, it was agreed to set up humanitarian corridors to allow refugees to flee Ukraine.
But proposed ceasefire attempts in the city of Mariupol collapsed at the weekend.
Russia announced new humanitarian corridors on Monday, but Ukraine branded the plans “immoral” as they would lead refugees straight into the arms of Russia and its close ally, Belarus.
Meanwhile, the mayor of the Ukrainian port city of Mykolaiv claimed that Russians dropped cluster bombs on residential buildings and a zoo on Monday morning.
Russia issued a list of demands on Monday, saying Ukraine must follow four criteria for its invasion to stop.
These included ceasing military action; changing its constitution to enshrine neutrality; acknowledging Crimea as Russian territory and recognising the separatist republics of Donetsk and Lugansk as independent territories.