U.S. Sen. Elizabeth Warren is sounding yet another alarm about the ills of cryptocurrency; this time focused on cryptocurrency mining operations in Iran that she claims are financing Hamas and other terrorist groups around the world.

In an open letter to the Biden Administration—co-signed by Sen. Angus King—Warren asked the secretaries of Defense and Treasury as well as the White House National Security Advisor about the administration’s efforts to “combat Iran’s rampant evasion of U.S. and international sanctions through cryptocurrency (crypto) mining.”

“Iran legalized the crypto mining industry in 2019,” Warren and King wrote. “In the five years since Iran has raised millions of dollars through mining crypto… a steady revenue source that allows it to purchase imports, move funds domestically and internationally, and fund Hamas and other terrorist organizations.

“This ongoing activity by the Iranian government threatens our national security,” the senators warn.


“Mining for energy-intensive blockchains like Bitcoin can allow countries to monetize energy resources, some of which cannot be exported due to sanctions,” the letter continued, citing an April 2022 International Monetary Fund (IMF) report.

Warren and King also mentioned a February 2024 Chainalysis report. “More than three percent of all inflows to Iranian crypto exchanges—and more than 29% of all Bitcoin inflows—are estimated to come from mining pools,” they wrote.

Warren and King enumerated several questions for the Biden Administration to answer regarding Iran's cryptocurrency activities. How much revenue has Iranian crypto miners generated since 2021? What share is collected by the government or its affiliates? And to what extent do these funds support terrorism or military activities?

The Senators also want to know what the administration has been doing to address the national security threats posed by Iran's alleged sanction-evading crypto activity.


“Unless we take action, Iran will continue to use crypto to fund attacks against Israel,” the senators said.

The letter to the White House is the latest salvo from Warren in her ongoing campaign to fight the use of cryptocurrency in illicit activities.

In December, Warren called for the Bank Secrecy Act to be updated to address the “threat” of crypto, claiming that North Korea is using cryptocurrency to fund its nuclear weapons program. Then in April, Warren asked the U.S. Department of Justice and Homeland Security to respond to questions on how Congress can help them fight Child Sexual Abuse Material (CSAM) funded with cryptocurrency.

Edited by Ryan Ozawa.

Daily Debrief Newsletter

Start every day with the top news stories right now, plus original features, a podcast, videos and more.