The U.S. Treasury Department lists the countries sanctioned by the Office of Foreign Assets Control in the Resources section of its website. The list includes countries and other organizations sanctioned by the Treasury Department.
From the U.S. Treasury Department main page, click on the section marked Resource Center. From there, scroll down and click on Financial Sanctions. In the Financial Sanctions section, scroll down to the section marked Sanctions Programs and Country Information, and click on Complete List of Sanctions Programs and Country Information. This section contains a list of the sanctions currently maintained by the OFAC. Sanctions imposed can include trade restrictions or blocking of assets.