Iran and the United States will hold their first bilateral talks in decades, it was announced Saturday, in a major step toward securing a comprehensive nuclear deal with the West.
The head to head discussions will take place in Geneva on Monday and Tuesday, Iran's foreign ministry said in a surprise statement carried by the official IRNA news agency.
A State Department official confirmed the meeting, noting the US delegation would be led by Deputy Secretary of State William Burns and Undersecretary Wendy Sherman, who is responsible for Iran negotiations.
The two-day meeting is the most senior direct bilateral contact on the nuclear issue so far, with Iran to be represented at vice foreign minister level.
The discussions in Geneva are also the first between Iran and the US to fall outside the P5+1 group of leading nations (Britain, China, France, Russia, the United States plus Germany) which is pursuing talks in the quest for a landmark nuclear agreement.
Iran and the US, at odds since the 1979 Islamic revolution and the hostage crisis that followed, have in the past year taken tentative steps on the path to rapprochement.
President Hassan Rouhani, a self-declared moderate elected last June, spoke by telephone with his US counterpart Barack Obama shortly after taking office.
Such a step had not occurred since the revolution and would have been considered unthinkable under Rouhani's predecessor Mahmoud Ahmadinejad, under whom relations with the West plummeted.
US Secretary of State John Kerry also briefly met Iran's Foreign Minister Mohammad Javad Zarif in Geneva last year.
The apparent thaw in relations is aimed at ending decades of enmity between the countries, with an accord on Iran's nuclear activities the apparent prize sought by the US and other world powers.
In return, Iran wants an end to wide-ranging economic sanctions imposed as punishment for pursuing its atomic program. The sanctions have devastated its economy in recent years.
In Saturday's announcement the foreign ministry also said two days of direct talks with Russia in Rome would immediately follow the talks with the US.
The two meetings, which immediately precede the next round of discussions between Iran and the P5+1, will be widely interpreted as an all-out diplomatic push to close glaring gaps between Tehran and the West over the Islamic republic's disputed nuclear programme.
The P5+1 and Iran meet in Vienna, between June 16-20.
Iran was also "working to arrange" other bilateral discussions with members of the P5+1 before the Vienna meeting, the foreign ministry said.
The negotiations are aimed at securing a comprehensive agreement on the Islamic republic's disputed nuclear programme ahead of a July 20 deadline imposed under an interim deal agreed last November.
Several rounds of talks have already been held in Vienna but the latest in mid-May ended with no apparent progress on a conclusive deal.
Iran has consistently denied it is seeking nuclear weapons but wants an independent atomic energy programme.
Following the last round in Vienna, Iran urged western powers to resist pressure from third parties not directly involved in negotiations over its nuclear activities, in a clear reference to Israel.
Israel and lawmakers in the US Congress have repeatedly warned against lowering the pressure -- in the form of economic sanctions -- on Iran.
Major issues between Iran and the P5+1 remain outstanding.
These reportedly include the scope of Iran's enrichment of uranium, which if further purified could be used to trigger a nuclear explosion, and its unfinished Arak research reactor, whose by-product waste could provide an alternative route to an atomic bomb.
Negotiators aim to nail down an exceedingly complex and lasting deal limiting Iran's atomic activities in exchange for the lifting of sanctions.
Failure could have calamitous consequences, potentially sparking conflict -- neither Israel nor the United States rules out military action -- and creating a nuclear arms race in the Middle East.