Maine’s independent senator wants the U.S. to try to limit Russian president Vladimir Putin and others in Russia from dodging economic sanctions by using cryptocurrencies.

Sen. Angus King said he is cosponsoring legislation that would seek to stop Putin and others from using digital assets to make an end-run on tough sanctions placed by the U.S.

He said the proposal would stop any Russian digital assets from being traded in U.S. jurisdictions.

He says the proposal would also include new cryptocurrency transparency requirements and give the Biden administration new powers to go after the digital assets.