The biggest threat to Putin is ultra-nationalists, a pro-Kremlin Russian MP said.
Oleg Matveychev said "ultra-patriots" could overthrow Putin over his army's performance.
"The situation is not so critical yet, but 2023 will be very dangerous," Matveychev said.
A leading Russian MP said that his country's "ultra-patriots" could try to overthrow President Vladimir Putin in frustration with their army's performance in Ukraine.
Oleg Matveychev - an MP with Russia's largest political party, United Russia, which backs Putin - said in an interview that the biggest threat to Putin is now supporters of the Ukraine war who are unhappy with the progress of the conflict, The Times of London reported.
He said that for Putin "the situation is not so critical yet, but 2023 will be very dangerous," the Times reported.
Matveychev is often referred to as the Kremlin's "spin doctor" due to frequent comments on behalf of top government officials.
However, his latest comments are unlikely to please those in the Kremlin.
Matveychev said that "ultra-patriots" in the country will likely put forward a candidate to run against Putin in next year's presidential elections, when Putin is set to run for a fifth term.
He added that the candidate would likely follow the playbook from a series of protests in Ukraine in 2013, which ended in Ukrainian President Viktor Yanukovych, who was allied with Russia, being ousted.
He referred to this as following "the Maidan scenario," referring to Independence Square in Kyiv, where those protests largely took place.
"An ultra-patriotic Maidan with a light dose of leftism, talk about corruption - these are a means to bring people out, and the trigger could be anything," he said, highlighting some of the battlefield setbacks in Ukraine.
Putin has become increasingly isolated from the rest of the world since his invasion of Ukraine in February 2022, with the West imposing further sanctions on Russia and even his longtime allies criticizing the war.
In Russia he's also faced backlash from pro-war figures, who are unhappy with the army's performance and want even more brutal tactics in Ukraine. A former Putin speechwriter said last month that a coup could happen in Russia as military generals are frustrated at their troops' defeats.
"As problems pile up in the country and the army, that the authorities are unable to solve, Putin is more steadily transforming in people's eyes from a great strategist to an ordinary, second-rate dictator," the speechwriter said.
