The Trump administration imposed new sanctions on North Korea last week, but one U.S. senator has said that the measures don’t go far enough in deterring the reclusive country’s efforts to steal cryptocurrencies.

The sanctions were unveiled on Feb. 23, targeting North Korea’s shipping and maritime trading industries. The goal, as stated at the time, is to disrupt the country’s ability to conduct energy-related imports and exports.

Senator Ed Markey of Massachusetts, however, took the administration to task that same day, arguing that the sanctions are insufficient for a number of reasons. Among those, he said, is a lack of cybercrime-related elements, specifically referring to steps taken by North Korea to hack exchange services and steal bitcoin and other cryptocurrencies.

Markey said in a statement:

“And despite North Korea being an avowed state-sponsor of cybercrime, the country’s illicit cyber activities are not addressed. Russia’s reported involvement in providing internet connectivity to the North Korean elite and the Chinese hosting of some North Korean cyberattacks go unmentioned. And these sanctions do nothing to restrict North Korea’s ability to steal cryptocurrencies, a principal means for Kim Jong Un’s regime to raise revenue for its military programs.”

Allegations that North Korea has moved to infiltrate cryptocurrency exchanges date back to last summer, coming in the wake of intrusions against a series of South Korea-based platforms. South Korean law enforcement officials ultimately came out publicly with their accusations.

According to reports from last month, government officials believe that tens of millions of dollars worth of cryptocurrencies have been stolen by North Korean actors.

North Korea flag and bitcoins image via Shutterstock