The team of Alexei Navalny, the imprisoned opposition leader in Russia, will from now on only take donations in cryptocurrencies, said Leonid Volkov, head of Navalny’s volunteer network.

In a video address to Navalny's supporters on Wednesday, Volkov said the activists are keeping on with their work despite the recent wave of repression against Navalny and his allies, and are still in need of financial support. But the traditional financial system, which can be fully monitored by the state, is a bad intermediary on which to rely, Volkov said.

"If the authorities are pushing us out of fundraising via the banking system, we will be patiently teaching everyone to use cryptocurrencies and learn ourselves," he said, adding:

"Cryptocurrencies are a real substitution for money; it's not a toy. Their advantage is that they are not controlled by any central banks or governments. So it's hard or even impossible for the governments to track them."

Volkov's bitcoin wallet dedicated to donations has received over 660 BTC since 2016, and more than one full bitcoin since April, according to the blockchain data.

Alexei Navalny, a vocal opponent of Russia President Vladimir Putin, was poisoned last autumn by a chemical weapon, then arrested after he survived. After his arrest, a series of protests ensued and bitcoin donations to the network of Navalny's allies surged.

In May, Navalny's Anti-Corruption Foundation (FBK) was labeled an extremist organization by a Russian court. Although the process is still ongoing, the organization disbanded in advance to avoid exposing activists to potential criminal charges, should the initial ruling stand.

Even occasional supporters of Navalny might be subject to persecution: A new draft bill introduced in the Russian parliament in May suggests that anyone linked to an extremist organization won't be able to run in any future elections.

Russian authorities have already taken a harsh stance against anyone backing Navalny. In May, a database of people who registered on a website dedicated to a protest rally in his support was stolen. Subsequently, participants were deanonymized and some lost their jobs.

In this situation, crypto can be a way for people to support Navalny's cause but avoid being reprimanded, Volkov said in the video.

"Crypto is not an illegal version of a bank transfer; it's a legal and safe replacement for cash. Cryptocurrencies, in fact, are very far away from criminal activities. They started as a mathematical game, but now even big companies and progressive entrepreneurs started using them," he said, pointing to Elon Musk as an example.

Volkov also gave a brief explanation about anonymity in crypto and recommended that people new to cryptocurrencies start with buying a small amount on a big centralized exchange. In the description of a video, there is a bitcoin wallet address, a link to the major centralized exchange Binance and the number of Volkov's account there for donations.

"If you're not planning to use crypto, it won't hurt to just have a wallet with some amount in it," he says in the video. "You don't have to buy a whole bitcoin. Try and see that it's not hard at all. No need to afraid of cryptocurrencies; very soon, they will become a part of our life just as ordinary money is. And if we can be one step ahead of the government in this, we should use this chance."