That the talks are even happening represents a historic moment, given the decades of enmity between the two countries since the 1979 Islamic Revolution and the U.S. Embassy hostage crisis.

Delegations from the United States and Iran on Saturday resumed "indirect" negotiations on a nuclear deal in Rome, with another round of talks set for next Saturday, after experts hash out technical matters Wednesday.

A second round of nuclear talks between the United States and Iran is underway, as what both sides are looking for in a deal begins to take shape. Delegations from both countries met in Oman last weekend for talks mediated by the Gulf Arab nation.