From the introduction to Iran Missile Tests and Sanctions (Feb. 8, 2017, IN10652):
On February 1, 2017, the Trump Administration announced that it was “officially putting Iran on notice” for recent actions that “threaten U.S. friends and allies in the region,” including the January 29 test of a ballistic missile and “weapons transfers [to groups such as Houthi rebels in Yemen], support for terrorism, and other violations of international norms.” The July 2015 multilateral nuclear agreement with Iran, the “Joint Comprehensive Plan of Action” (JCPOA), does not restrict Iran’s ballistic missile programs. However, U.N. Security Council Resolution 2231, which endorses the JCPOA, prohibits Iran from exporting weaponry and “call[s] upon” Iran “not to undertake any activity related to ballistic missiles designed to be capable of delivering nuclear weapons, including launches.” Yet, Iran has conducted several ballistic missile tests since JCPOA Implementation Day on January 16, 2016—the day Resolution 2231 formally took effect.
For a timely comprehensive overview of US sanctions against Iran see Iran Sanctions (Apr. 14, 2017, RS20871). — Joe