On December 20, 2017, the President of the United States issued Executive Order 13818 blocking the property of designated persons and entities involved in serious human rights abuse or corruption.
Executive Order 13818 blocks the property and interests of the persons and entities listed in the annex of the order, in addition to prohibiting financial transactions and unrestricted entry into the United States. The E.O. implements the Global Magnitsky Human Rights Accountability Act (signed into law on December 23, 2016), which targets human rights abusers and corrupt actors globally.
The E.O. became effective on December 21, 2017.
The Executive Order can be found here:
FAQs issued by the Treasury Department can be found here:
https://www.treasury.gov/resource-center/sanctions/Programs/Documents/12212017_glomag_faqs.pdf