An aide to Ukrainian President Volodomyr Zelensky says Vladimr Putin is “living in fear for his life'” because the Russian military has retreated.

Earlier this month, Russia declared its abandonment of the Kherson region, a humiliating setback for Putin and a potential turning point in the conflict, which has dragged on for nine months.

The loss of Kherson, the only regional capital Russia had captured in the conflict, dealt a heavy blow to plans to establish a land corridor to Crimea and secure a water supply to the Russian-controlled territory.

Moscow could be preparing a fresh offensive from Belarus to the north of Ukraine, after the liberation of Kherson. Putin’s troops retreated from Kyiv early in the war after encountering fierce resistance.

According to Oleksiy Arestovich, an adviser to Ukraine’s chief of staff, Putin is terrified because Russia has no mercy for tsars who lose wars.

“He is fighting for his life now. If he loses the war, at least in the minds of the Russians, it means the end. The end of him as a political figure. And possibly in the physical sense.”

Since the annexation of Crimea and the outbreak of war in eastern Ukraine, Russian President Vladimir Putin’s approval rating has declined. A recent poll by the Levada Center, an independent Russian polling organization, showed that only 38% of Russians approve of Putin’s job performance—the lowest rating since he took office in 2000.

Many Russians are growing increasingly disillusioned with Putin’s policies, and there is a growing demand for change. This sentiment is especially strong among young people. Another survey found that 70% of Russians aged 18-24 want Putin to step down.