Russian journalist and activist Vladimir Kara-Murza addresses a press conference on August 2, 2024 in Bonn, Germany, one day after being released from Russia as political prisoner in one of the biggest prisoner swaps between Russia and the West since the end of the Cold War. (Ina Fassbender/AFP via Getty Images)

(NEW YORK) -- When the United States' prisoner exchange with Russia, the largest since the Cold War, happened in early August, one of Russian President Vladimir Putin’s harshest critics became a free man. Vladimir Kara-Murza had been sentenced to 25 years in prison on treason charges after speaking out about the war in Ukraine.

Kara-Murza spent two and a half years locked up in different Russian prison colonies, spending 11 months of that time in solitary confinement. On Aug. 1, in a multi-country prisoner swap, the Russian-born Kara-Murza was freed along with Americans Evan Gershkovich, Paul Whelan and Alsu Kurmasheva -- all of whom were sentenced on espionage charges and for allegedly spreading false information.

On Monday, in his first interview with ABC News since being released, Kara-Murza spoke to ABC News Live anchor Diane Macedo about how he is adjusting to a life of freedom.

“It still feels very unreal … just a few weeks ago, I was so confident that I would end my life in Putin’s Siberian prison,” he said. “And now I'm at home with my family, so it's … something out of the books.”

That choice of words was appropriate, given Kara-Murza’s education as a historian and his study of the Soviet dissident movement. He highlighted President Joe Biden’s role in the exchange and what it tells us about the reality of politicians’ work versus the public perception.

“Only four American presidents in history -- two Republicans, Ford and Reagan, and two Democrats, Carter and now Biden -- have negotiated such prisoner releases, prisoner exchanges, to help save prisoners of conscience from the Soviet or Russian gulag,” he said.

“In this day and age, when there is a sort of cynical stereotype that all politics is about expediency and realpolitik, and that there's no room for principle or value anymore, I think it is important to sort of pause and note that sometimes the leaders of Western democracy don't just pay lip service to protecting human rights, but actually do it in practice too,” he added.

Kara-Murza may be free, but he noted that adjusting to that reality has been challenging -- especially since he spent nearly 11 months straight in solitary confinement.

“By international law, by the United Nations, a minimum standard rules on the treatment of prisoners, solitary confinement longer than 15 days is officially considered to be a form of torture -- degrading and inhumane treatment -- because [the philosopher] Aristotle said that human beings are social animals,” he said. “We need human interaction just as much as we need oxygen to breath or food to eat or water to drink.”

He was also forbidden from calling his wife and three children, or going to church, he said. He compared the experience to the 1993 movie Groundhog Day, where a character is trapped and forced to repeat the same day over and over.

“It's endless, meaningless and exactly the same. Wake up at 5 o'clock in the morning … you attach your bunk to the wall. And then essentially, you just sit in your small cell,” he said of this period of confinement.

Kara-Murza said he was allowed out for 90 minutes for a “small so-called walk” around a covered prison courtyard that wasn’t much bigger than his cell, he noted. Beyond that, he told ABC he was given a pen and paper for only 90 minutes each day -- the only window of time he had to prepare for court hearings, read and write letters to family, friends and journalists.

Even though he was fortunate enough to be part of the prisoner exchange, Kara-Murza noted that hundreds remain in Russian prisons for “publicly opposing Putin's dictatorship and his aggressive war against Ukraine” along with thousands of Ukrainian prisoners of war.

Kara-Murza highlighted the fact that this August marks the 25th anniversary of Putin being appointed as Russia’s acting prime minister by then-President Boris Yeltsin.

“So there's an entire generation of people in my country, in Russia, that have grown up not knowing any other political reality,” he said. “And … we know what it entails to be in opposition to Vladimir Putin's regime.”

Kara-Murza said he was poisoned twice by agents of Russia's FSB (Federal Security Service), prior to being sentenced to 25 years in prison.

“I care about my country. I love my country," he said. "And I think Russia deserves a much better future than to be in the hands of an authoritarian, aggressive, murderous, illegitimate dictatorship.”

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