Cryptocurrency analysts say at least $13.7m (£10.2m) has so far been donated to the Ukrainian war effort through anonymous Bitcoin donations.
Researchers at Elliptic, a blockchain analysis company, say the Ukrainian government, NGOs and volunteer groups have raised the money by advertising their Bitcoin wallet addresses online.
More than 4,000 donations have been made so far, with one unknown donor gifting Bitcoin worth $3m to an NGO.
The median donation is $95.
On Saturday afternoon, the official Twitter account of the Ukraine government posted a message: "Stand with the people of Ukraine. Now accepting cryptocurrency donations. Bitcoin, Ethereum and USDT."
It posted addresses for two cryptocurrency wallets which collected $5.4m in Bitcoin, Ether and other coins within eight hours.
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The Ukrainian Digital Ministry says the latest call for donations is to "help Ukraine armed forces", but would not elaborate on how the money would be spent.
Elliptic founder Tom Robinson told the BBC: "Whereas some crowdfunding and payments companies have refused to allow donations to be made to groups supporting the Ukrainian military, cryptocurrencies have emerged as a powerful alternative."
On Friday, fundraising platform Patreon announced that it had suspended the donation page for "Come Back Alive", a Ukrainian NGO that has been raising money for Ukrainian forces in conflict zones since 2014.
Patreon said the page violated the company's policies, saying in a statement: "We don't allow Patreon to be used for funding weapons or military activity."
Cryptocurrency fund raising is becoming an increasingly prominent part of modern conflicts around the world.
Scammers appear to be also be taking advantage of the current situation in Ukraine, though, by tricking unsuspecting users.
Elliptic says at least one social media post was found to copy a legitimate tweet from an NGO, but with the author swapping the Bitcoin address, presumably for one of their own.