Mikhail Khodorkovsky, a Russian businessman exiled for nearly a decade, says that those still living in his home country who oppose the invasion of Ukraine should work to "sabotage" it from the inside.

Khodorkovsky lives in London after spending 10 years in jail from 2003 to 2013. He told The Guardian in a story published Monday that President Vladimir Putin's invasion of Ukraine has changed the agenda for Russia's political opposition. "Armed resistance" may at some point play a role, he said.

"We need to explain to people what they can do, persuade them that they should do it, and also help people if, as a result, they end up in a dangerous situation," Khodorkovsky told the Guardian.

Each person should consider their own tolerance for risk, he said, noting that potential acts could range from painting anti-war graffiti to sabotage of train deliveries connected to the war or burning down conscription offices.

"But we are very clearly against terrorist methods that harm unarmed people," he added, a reference to the car-bomb killing of Darya Dugina, daughter of top Putin ally Alexander Dugin. Russia claims the attack was planned by Ukraine with the aid of Russian partisans, but Ukraine has denied any involvement.

Khodorkovsky said it is vital for the west to realize that many Russians still living in the country oppose Putin so that when he is eventually defeated the country can become more pro-western and democratic.

"This is a nightmare, but this nightmare does not mean that Russia and Europe have separated forever," he said. "It’s extremely important that in this difficult emotional background, we keep a sound mind, pragmatism and a vision of the future, of a democratic, European Russia."

Khodorkovsky rose up through the Youth Communist League during the time of Mikhail Gorbachev’s reforms, becoming the richest businessperson in Russia as chairman of Yukos oil company.

In his new book, The Russia Conundrum, he talks about early meetings with Putin where he was convinced the new leader was pro-freedom.

"His technique is to look at you and mirror what you are saying … He’s a chameleon who leaves everyone thinking he’s on their side," he says in the book.

But, he says, "I wasn’t sharp enough to see it. He has that professional KGB skill of adapting to his interlocutor, but he also just has a personal talent for it … Back then, he didn’t feel stable in his position and he didn’t want to create enemies who would unite against him. Of course he never had any liberal views."

Khodorkovsky was arrested in 2003 on what are seen as political charges after he publicly criticized government corruption during a meeting with Putin and said he would fund opposition parties.

Today, he tells The Guardian, lifelong friendships are severed over the war.

"Imagine, you know people since you were both 7 years old, and now you’re both nearly 60 and you just can’t speak to them," he said.

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