[caption id="attachment_155653" align="alignright" width="204"] Head of the Atomic Energy Organization of Iran Ali Akbar Salehi (L) and US Energy Secretary Ernest Moniz hold talks in the Swiss city of Lausanne March 15, 2015.[/caption]
U.S. energy secretary, Iranian atomic agency chairman hash out details amid the diplomacy


LAUSANNE, Switzerland—Two physicists with strong ties to the Massachusetts Institute of Technology—one American, one Iranian—are playing make-or-break roles in negotiations aimed at forging an agreement to curb Iran’s nuclear program by the end of this month.

Ernest Moniz, the U.S. energy secretary, was an assistant professor in MIT’s physics department while Ali Akbar Salehi, now chairman of the Atomic Energy Organization of Iran, was studying for his doctorate in nuclear engineering, which he received in 1977.

Today, the two are ensconced in exhaustive, one-on-one discussions that aim to ensure that Iran won't maintain a capacity to quickly produce atomic weapons, according to U.S. and Iranian officials.

Their introduction into the diplomacy last month signaled stepped-up efforts by Washington and Tehran to try to find technical solutions to what’s being described as among the most complex arms-control negotiations ever pursued.

Mr. Salehi said in Lausanne on Tuesday that he was optimistic a deal can be reached shortly, and said only one technical issue remained as a stumbling block.

“We hope that we reach a common ground on this final item,” he told reporters. “If we do, we can say that on technical issues things are clear to both sides.”

Mr. Moniz and Mr. Salehi never met when they were at MIT during the mid-1970s, according to senior U.S. and Iranian officials.

Also at MIT at the time was Israel’s future prime minister, Benjamin Netanyahu, who was studying architecture, business management and political science.

All this was before the 1979 revolution that ushered in Iran’s clerical government and more than 30 years of U.S.-Iranian animosity.

Messrs. Moniz and Salehi have held about a dozen face-to-face meetings over the past month in the Swiss lakeside cities of Geneva, Montreux and Lausanne, including two this week.

The two men cast vastly different profiles: Mr. Moniz as the college professor with his shoulder-length silver hair; Mr. Salehi, the consummate Iranian revolutionary bureaucrat, with a closely cropped beard and tieless business suit.

“The discussions with him have been very, very professional,” said a senior U.S. official briefed on Mr. Moniz’s meetings with the Iranian scientist. “He’s extremely professional.”

Among issues the two men are seeking to resolve: the future size of Iran’s nuclear-fuel production capacity; the status of an Iranian heavy-water reactor that is capable of producing weapons-grade plutonium; verification mechanisms to guard against Iran cheating; and the future size of Iran’s stockpiles of nuclear materials.

Mr. Moniz, 70 years old, hopes to constrain Iran’s nuclear program. Mr. Salehi, five years the junior, represents an Iranian nuclear establishment that seeks to retain as much of its infrastructure as possible.

U.S. and European officials said they were initially unnerved by Mr. Salehi’s appearance on the diplomatic stage, 18 months into the talks.

A speaker of Persian, Arabic (he was born in Karbala, Iraq) and English, Mr. Salehi was a central player in the hard-line government of former Iranian President Mahmoud Ahmadinejad, serving as both foreign minister and then chief of the Atomic Energy Organization of Iran, known as the AEOI.

United Nations inspectors have also voiced concerns about Mr. Salehi’s role in alleged clandestine nuclear work conducted by Iran.

The physicist served in the 1980s and early 1990s as the chancellor of Sharif University, widely viewed as Iran’s top engineering school. It was among the institutions targeted by Western sanctions.

The U.N.’s nuclear watchdog, the International Atomic Energy Agency, tracked the school’s secret procurements of equipment and academic research that could be used in a nuclear-weapons program, according to former IAEA officials.

“Few people in Iran know more about Iran’s nuclear program from its beginnings than Dr. Salehi,” said Olli Heinonen, a former chief of the IAEA’s nuclear inspections unit.

Iran denies it or Mr. Salehi have been involved in any nuclear-weapons research. But IAEA officials said they still haven’t resolved allegations that Iran in the past has worked on weaponizing nuclear material.

U.S. and European officials now say that, despite their reservations, they view Mr. Salehi’s presence at the talks as crucial for their efforts. He has significantly more technical knowledge than Foreign Minister Javad Zarif, Tehran’s lead negotiator. And Mr. Salehi may have more authority from Supreme Leader Ayatollah Ali Khamenei to actually cut a deal, they said.

“His presence has been very helpful,” said a senior European official taking part in the diplomacy.

Mr. Moniz, meanwhile, is backed in the talks by a U.S. nuclear establishment that has thousands of scientists devoted to studying and understanding atomic weapons.

U.S. officials said the energy secretary and his team are in regular consultations with experts from top nuclear laboratories, including Lawrence Livermore in California, Oak Ridge in Tennessee, and Sandia in New Mexico.

One focus of these labs, according to U.S. diplomats, is to develop a scientific model of how long it would take Iran to “break out” and produce enough weapons-grade fuel for a nuclear weapon, if it made the political decision to push forward.

U.S. negotiators are trying to extend Iran’s breakout time to at least a year.

American officials said this week that it is still unclear if Mr. Salehi and the Iranian government are willing to take these steps, with two weeks before the diplomatic deadline of March 31.

“You get to a point in a negotiation where you’ve discussed all the issues, you’ve discussed them many times, you know all the elements,” said a second senior U.S. official involved in the talks. “And it’s not like getting to the decisions is going to be easier if you wait another month.”

This article was written by Jay Solomon for The Wall Street Journal on Mar. 17, 2015. Jay Solomon writes about foreign affairs and national security from The Wall Street Journal's Washington DC bureau. His coverage areas include international diplomacy, nuclear weapons proliferation, counter-terrorism and Middle East and Asian affairs.