The key opponent of Russian leader Vladimir Putin died in February in a penal colony, where he had been held in harsh conditions
The key opponent of Russian leader Vladimir Putin died in February in a penal colony, where he had been held in harsh conditions AFP

Kremlin critic Alexei Navalny's posthumous memoir will be released in October, chronicling his 2020 nerve agent poisoning and life in a brutal Russian prison camp, the US publisher of the book said Thursday.

The key opponent of Russian leader Vladimir Putin died in February in a penal colony, where he had been held in harsh conditions.

Titled "Patriot," the book will be released on October 22, publisher Knopf said in a statement, while his widow confirmed the book would also be issued in Russian.

"It is the full story of his life: his youth, his call to activism, his marriage and family, and his commitment to the cause of Russian democracy and freedom in the face of a world super-power determined to silence him," Knopf said.

"It expresses Navalny's total conviction that change cannot be resisted and will come."

Navalny's widow, Yulia Navalnaya, who has taken over his mantle in exile, has accused Putin of killing her husband. She confirmed the book would be published in more than 10 languages, including Russian.

"This is not at all how I imagined Alexei would write his biography. I thought we'd be in our eighties and that he'd sit at his computer by an open window and write," said Navalnya.

"After the poisoning attempt in 2020, everyone told him: 'Alexei, you should write a book.' And he dismissed it out of hand. I mean, what kind of biography do you write at 44?

"Barely more than half his life had passed. He was in no hurry, he still had so much to do. And things happened as they happened -- horribly and very, very unfairly. As it turns out there was no other half to come."

Navalny began writing the memoir after the 2020 poisoning, which led to his hospitalization. He returned to Russia the next year, and was jailed.

His death has robbed Russians opposed to Putin of their most charismatic figurehead at a time when authorities have crushed the last remnants of dissent.

The crackdown has intensified since the Kremlin launched its full-scale hostilities against Ukraine in 2022.

Former KGB officer Putin secured a new six-year term in power in the face of no genuine challenger at elections in March.