Jailed Russian opposition leader Alexey Navalny on Friday took aim at Russia's "corrupt" elite that placed President Vladimir Putin in power.

In what he called "My Fear and Loathing" -- his first lengthy statement since he was convicted of extremism and sentenced to 19 years in prison by a court in Moscow last week -- Navalny said he hated self-serving Russian officials, so-called "reformers" of the 1990s who are concerned only with "their own wealth."

"That is why I can't help it and I fiercely hate those who sold, drank, and wasted the historical chance that our country had in the early 1990s," Navalny said.

"I hate Yeltsin, [...] Chubais and the rest of the corrupt family who put Putin in power," he said, referring to former Russian President Boris Yeltsin and former high-level Russian official Anatoly Chubais.

"Is there any other country where so many ministers of (a) government of reforms became millionaires and billionaires? I hate the authors of the most stupid authoritarian constitution, which they sold to us idiots as democratic, even then giving the president the power of a full-fledged monarch," he added.

Navalny blamed the Russian leadership in power after the collapse of the Soviet Union for "not even trying to make obvious democratic reforms."

He called the election in Russia in 1996 "fraudulent" and "one of the most dramatic turning points in Russian modern history," noting that back then "the general unfairness of the election" didn't bother him.

But he said "Russia will still have a chance" to turn things around into the democratic direction.

"This is a historical process. We will again be at the crossroads," he said.

However, he admitted there are times when he jumps up "in horror and cold sweat" at night in prison and feels that Russia "had a chance again, but it again went the same way as in the 90s."

Navalny was last week sentenced to 19 years in jail on a raft of extremism charges in what was widely seen as a political move by Moscow to silence him.

He was already serving sentences totaling 11-and-a-half years in a maximum security facility on fraud and other charges that he says were trumped up.

Before his incarceration, he was taken from Russia to Germany in August 2020 for treatments after he was poisoned with the Soviet-era nerve agent Novichok.

Moscow has denied involvement in the poisoning, with Putin himself saying in December 2020 that if Russian security services had wanted to kill Navalny, they "would have finished" the job.