"With the nuclear issue unresolved, the domestic unrest in Iran that has occurred since alleged wide-scale fraud was committed in Iran's June 12, 2009, presidential election has presented the Administration with a potential choice of continuing the engagement or backing the opposition 'Green movement.' [...] Even at the height of the Green movement protests, the Obama Administration did not forego diplomatic options to blunt Iran's nuclear progress and says it remains open to a nuclear deal if Iran fully accepts a framework Iran tentatively agreed to in multilateral talks on October 1, 2009. However, Iran did not accept the technical details of this by the notional deadline of the end of 2009, nor has it adequately responded to international concerns about possible work on a nuclear weapons program. These concerns have sparked renewed multilateral discussions of more U.N. sanctions. New sanctions under negotiation would target members and companies of Iran's Revolutionary Guard Corps, which is not only a pillar of Iran's nuclear program but is also the main element used by the regime to crack down against the protesters. [...] Separate U.S. efforts to persuade European governments to curb trade with, investment in, and credits for Iran, and to convince foreign banks not to do business with Iran, are intended to compound the U.N. pressure. Each chamber in the 111th Congress has passed separate legislation to try to curb sales to Iran of gasoline, which many Members believe could help pressure Iran into a nuclear settlement or undermine the regime's popularity even further."
CRS Report for Congress, RL32048