The last four clandestine meetings, held since Iran's reform-minded President Hassan Rouhani was inaugurated in August, produced much of the agreement later formally hammered out in Geneva, said three senior Administration officials.
At the President's direction, the US began a tentative outreach shortly after his inauguration in January 2009. Obama and Iran's Supreme Leader, Ayatollah Ali Khamenei, exchanged letters, but the engagement yielded no results. That outreach was hampered by Iran's hardline former President, Mahmoud Ahmedinejad, whose re-election that year led to a violent crackdown on opposition protesters.
Efforts to win the release of US hikers in Iran got the clandestine talks going. Oman's Sultan Qaboos was a key player, facilitating their eventual release and then offering himself as a mediator for a US-Iran rapprochement.
Officials described those early contacts between mid-level officials as exploratory discussions focused on the logistics of setting up talks at a higher level. The discussions happened through numerous channels, including face-to-face talks at undisclosed locations. They included exchanges between then US Ambassador to the United Nations Susan Rice, now Obama's national security adviser, and Iran's envoy to the world body. National Security Council aide Puneet Talwar was also involved.
The talks took on added weight eight months ago, when Obama sent Burns, Sullivan and five other officials to meet their Iranian counterparts in Muscat. Obama sent the group shortly after the six powers opened a new round of nuclear talks with Iran in Almaty, Kazakhstan, in late February. At the time, those main nuclear negotiations were making little progress, and the Iranians had little interest in holding bilateral talks with the US on the sidelines out of fear that the discussions would become public.
The US officials characterised the Iranian attendees as career diplomats, national security aides and experts on the nuclear issue who were likely to remain key players even after the country's elections. Beyond nuclear issues, the officials said, the US team at the March Oman meeting also raised concerns about Iranian involvement in Syria, Tehran's threats to close the strategically important Strait of Hormuz and the status of three Americans detained in the country.
Rouhani's election in June on a platform of easing sanctions crippling Iran's economy and stated willingness to engage with the West gave a new spark to the US effort, the officials said. Two secret meetings were organised immediately after Rouhani took office in August, with the specific goal of advancing the stalled nuclear talks with world powers. Another pair of meetings took place in October. Burns and Sullivan led the US delegation at each of those sessions, and were joined at the final secret meeting by chief US nuclear negotiator Wendy Sherman.
The officials said they were sure the outreach had the blessing of Khameni, but would not elaborate.
After an Obama-Rouhani phone call in September the US began informing allies of the secret talks with Iran. Obama handled the most sensitive conversation himself, briefing Israeli Prime Minister Benjamin Netanyahu on September 30 at the White House.
At this month's larger formal nuclear negotiations between world powers and Iran in Geneva, Burns and Sullivan showed up as well, but the State Department went to great lengths to conceal their involvement, leaving their names off the official delegation list. They were housed at a different hotel from the rest of the team, used back entrances to come and go from meeting venues and were whisked into negotiating sessions from service lifts or unused corridors only after photographers left.
Key points of nuke pact
Iran and six world powers have reached agreement on curbing the Iranian nuclear programme in exchange for limited sanctions relief.
President Barack Obama said the deal was an important first step toward a comprehensive solution. Obama said if Iran did not meet its commitments during a six-month period, the US would "ratchet up the pressure".
He said the substantial limitations under the agreement "cut off Iran's most likely paths to a bomb". Some key points in the agreement:
Halting uranium enrichment above 5 per cent
This would keep Iran's enrichment level well below the threshold needed for weapons-grade material, which is more than 90 per cent enrichment. Uranium enriched to 5 per cent is adequate to make fuel for Iran's lone energy-producing reactor in Bushehr.
'Neutralise' Iran's stockpile of 20 per cent enriched uranium
This level of enrichment is within several steps of reaching weapons grade. Eliminating the stockpile eases Western concerns that Iran possibly could move quickly towards a nuclear weapon. Iran can either convert the 20 per cent uranium into reactor-ready fuel, which effectively blocks it from further enrichment. Or Iran can dilute the material to levels below 5 per cent enrichment. Allowing Iran to use the stockpile for domestic purposes is an important political takeaway for Tehran.
No new centrifuges
This effectively caps Iran's enrichment capacities for the next six months. Centrifuges are used to turn concentrated uranium into nuclear fuel. Iran is allowed to keep its two main enrichment facilities in operation. Iran's Government would have faced huge backlash from hardliners at home if either of the labs were forced to shut down.
Suspend work at the Arak reactor
The planned Arak reactor in central Iran is a "heavy water" plant, which uses a molecular variant of water as a coolant and can run on non-enriched uranium. It also produces a higher degree of plutonium byproduct, which could be extracted and potentially used in weapons production.
- AP