Vladimir Putin is at growing risk of being ousted in a coup led by his own security services, a Russian whistleblower has claimed.
Putin ordered his forces to invade Ukraine four weeks ago, but Western intelligence officials have repeatedly claimed military action has stalled because by poor leadership, strategic errors and fiercer than expected resistance from the Ukrainians.
Ukraine has managed to cling on and maintain control of major cities, including the capital of Kyiv.
Putin and his acolytes continue to claim the invasion is going to plan, but widespread protests in Russian cities have signalled discontent in his decision to launch war on a neighbouring country.
Now an exiled Russian human rights activist, Vladimir Osechkin, has said information from an unnamed source within Russia's Federal Security Service (FSB) suggests unrest is growing within the service.
Osechkin, who is wanted in Russia for his work exposing abuse in Russia's prisons, told The Times Putin is being blamed for Russia's inability to claim Ukraine, and senior figures are beginning to become disillusioned with the war over increasingly oppressive sanctions brought in by the West which are biting at the lives of ordinary Russians.
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"For 20 years Putin created stability in Russia. FSB officers, policemen, state prosecutors — those people inside the system — were able to live good lives,' Osechkin told the newspaper.
"But now, with Western sanctions, that has gone. Russia's economy has been crippled and the value of the Rouble has plummeted. Having grown accustomed to a better life, the FSB agents don't want to 'go back to the Soviet Union", Osechkin said.
He claimed the source has said agents are willing to change the whole system in the hope of clawing back their comfortable lives - even if that means ousting their President.
The longer the war goes on, they added, the more likely a coup could be.
Osechkin added: "For every week and every month that this war continues, the possibility of a rebellion by those in the security services increases."
Ukrainian authorities have claimed between 10-15,000 Russian troops have been killed in Ukraine - which if true would be the highest toll since the Second World War.
While the number has not been independently verified, a Nato source put the numbers of Russian soldiers killed at between 7,000 and 15,000
An anonymous officer from Nato said on Wednesday that battlefield casualties suffered by Russia are thought to total between 30,000 and 40,000 since Putin launched his invasion on February 24.
British military intelligence said on Thursday that "Russian forces have almost certainly suffered thousands of casualties during their invasion of Ukraine."
In an effort to bolster their troops, Russia is likely looking at bringing reservists and conscription, further intelligence has suggested.
An update added: "Russia is likely now looking to mobilise its reservist and conscript manpower, as well as private military companies and foreign mercenaries, to replace these considerable losses."
While Putin has not yet managed to gain control over Ukrainian citizens, he has been driving them out of the country in their millions.
The UN has estimated 3.5 million people have now fled to safer neighbouring nations, and a further 6.5 million have been displaced within Ukraine.
There is little sign of Ukraine's resistance wilting, either. Kyiv mayor and former heavyweight world champion boxer Vitali Klitschko told Yahoo News he thought Putin was "sick" for deciding to invade Ukraine.
Asked what he would say if Putin was in front of him, Klitschko said: “No reason to talk to him. He’s sick, he’s unhealthy. Everything that I see in my home country… [he’s] just an unhealthy man.”
He pointed to the destruction of cities such as Mariupol and killing of civilians, including six children in Kyiv.
“I have just one message to the Russians: you’re the aggressors, you’ve come to our country. Ukraine was always a friendly nation, a peaceful country. Right now, we have no choice but to fight and defend. The message to the Russians: go away from Ukraine. Go back home. You have nothing to find in our country. It’s our home.”
He repeated: “Stop the war. Stop the war. Go away from Ukraine. Main message.”