5 countries with the longest ongoing US sanctions

Starting in 1967 when Sudan broke diplomatic ties with the US following the outbreak of the Arab-Israeli war, relations have been strained between the two countries. Long accused of supporting terrorists, Sudan backed Iraq in its invasion of Kuwait in 1990, and reportedly provided sanctuary and assistance to terrorist groups including Carlos the Jackal, Osama bin Laden, and Abu Nidal.
 
In 1997 President Bill Clinton imposed comprehensive economic, financial, and trade sanctions on Sudan because of the country’s support for international terrorism, efforts to destabilize neighboring governments, and myriad human rights violations including slavery and the denial of religious freedom. In 2005 and 2006 the United Nations issued two resolutions augmenting the international response to Sudan, particularly the Darfur region. The UN called on member states to take measures against those responsible for the continuing conflict and violence against women and civilians.
 
The US maintains a number of sanctions on Sudan, though the Obama administration expanded diplomatic relations and relaxed some restrictions in 2010. As of July 2011, restrictions were lifted from South Sudan, allowing the US to provide assistance and engage in business and trade. It is believed that current sanctions on Sudan could impact South Sudan, including restrictions on the oil and financial sectors in the North.