The U.S. cut diplomatic ties with Iran in 1979 after militant students stormed the embassy in Tehran.
This year, President Obama and U.S. allies abroad imposed sweeping economic sanctions on Iran over its opaque nuclear program. The value of Iranian currency plummeted.
Now, Iran's foreign minister says direct talks -- between the U.S. and Iran -- are possible. The White House has not responded.
The Government Accountability Office published one study on the petroleum sanctions this month. They plan to release a second in the coming months.
Thomas Melito, director of international affairs and trade issues at the GAO, discussed the first study on Capital Insider.