With the conclusion of the interim nuclear agreement in Geneva, the Associated Press has released details of secret high-level talks between Iran and the US since March.

President Obama personally authorized the talks, held in Oman and elsewhere. Deputy Secretary of State William Burns and Jake Sullivan, Vice President Joe Biden’s top foreign policy adviser, met at least five times with Iranian officials.

Information about the discussions was withheld from US allies, including Israel, until September.

Three “senior Administration officials” said the last four meetings were held after President Rouhani was inaugurated in August. They said the sessions produced much of the interim agreement negotiated and agreed in the Geneva talks between Iran and the 5+1 Powers.

The officials would not give the names of the Iranian representatives, but said they were career diplomats, national security aides, and experts on the nuclear issue.

The officials said the March talks, building on the role of Oman’s Sultan Qaboos in negotiations such as the release of three American hikers from an Iranian prison in 2011, tried to break the deadlock in high-level talks that resumed in Kazakhstan in February.

They said the meeting also discussed Iranian involvement in Syria, Tehran’s threats to close the Strait of Hormuz, and the status of Robert Levinson, a missing former FBI agent who the U.S. believes was abducted in Iran, and two other Americans detained in the country.

Two secret meetings were organized immediately after Rouhani took office in August. Another pair of meetings took place in October. Lead US nuclear negotiator Wendy Sherman attended the final session.

Tbe US only began informing its allies after a phone call between Obama and Rouhani, who was in New York for the United Nations General Assembly, in late September. The US President briefed Israeli Prime Minister Benjamin Netanyahu during a September 30 meeting at the White House, telling him about the two meetings in the summer.

After telling Netanyahu about the secret talks, the United States then briefed the other members of the 5+1 Powers.