When President Barack Obama first began negotiating a nuclear deal with Iran, he was encouraged by the existence of an obscure religious ruling from the country’s supreme leader: In a fatwa, Ayatollah Ali Khamenei declared that developing or using nuclear weapons is against Islam.

Whether the edict was sincere or simply a cover story, a senior administration official told POLITICO at the time, it could at least provide the Iranian regime with cover to explain a nuclear deal to hard-liners demanding to know why Iran was not relentlessly pursuing The Bomb.


But as a June 30 deadline for a nuclear deal closes in, Khamenei’s Islamic decree has emerged as a major obstacle to a nuclear deal, say analysts and sources close to the talks. It turns out that the fatwa has turned what was once a key Western demand — that Tehran fully disclose its past research into nuclear bomb technology — into a potential deal-breaker.

The issue of that previous secret research — separate from the uranium enrichment now underway in sight of international monitors — is among the toughest issues as the U.S. and five other world powers try to strike a long-term agreement with Iran this summer.

It came to a head last week when Secretary of State John Kerry seemed to suggest that the U.S. would not demand a full accounting from Iran of all its military nuclear research before concluding a nuclear deal with Tehran that lifts economic sanctions. International inspectors have identified 11 areas of concern that Iran has failed to clarify, many of them based on Western intelligence — reportedly including a laptop smuggled from Iran with files that detail the bomb-making research. Iran insists it has never pursued a nuclear bomb.

Speaking to reporters on June 16, Kerry said the U.S. is “not fixated on Iran specifically accounting for what they did at one point in time or another. We know what they did. We have no doubt.”

“What we’re concerned about,” he added, “is going forward.”

Kerry’s words riled Republicans in Congress and pro-Israel leaders who slammed them as a dangerous concession to Iran.

“The administration should walk away and make good on their promise that no deal is better than a bad deal if there is anything less than full disclosure up front,” Senate Foreign Relations Committee chairman Bob Corker said in a statement on Friday.

“If this issue isn’t resolved, expect a five-alarm fire” in Congress, added a Democratic Senate foreign policy aide.

The State Department quickly insisted that there has been no shift in the U.S. position, which is that sanctions can be lifted only after Iran “addresses” the International Atomic Energy Agency’s concerns about its past activities.

But addressing the IAEA’s concerns does not necessarily mean a full public confession. Reaching a deal may require finding a compromise solution that allows Iran to continue denying that it ran a secret Manhattan Project while granting the IAEA enough information to satisfy the nuclear watchdog agency that it understands the nature of Iran’s past program.

“It is not necessary, nor do I think it is realistic, to expect that Iran will admit that it was conducting nuclear weapons research activity,” says Kelsey Davenport, director for nonproliferation policy at the nonpartisan Arms Control Association, which has supported Obama’s nuclear diplomacy.

A central reason, sources say, is the humiliation such a disclosure would cause for Khamenei, who issued the October 2003 fatwa stating that Islam forbids the production, stockpiling or use of weapons of mass destruction.

Obama himself invoked the fatwa in a March video statement observing the Iranian new year, or “Nowruz.”

“Khamenei will never admit that Iran conducted weapons-related research,” said Karim Sadjadpour, an Iran expert at the Carnegie Endowment for International Peace. Doing so, he said, would “contradict the regime’s long-standing assertion that nuclear weapons are against Islam.”

Some experts said the issue is as much political as it is religious, however: Iran appears determined never to concede that it did anything to warrant punitive international sanctions, and to maintain its posture as a victim of Western aggression. “Our program always has been — and always will be — exclusively peaceful,” insisted Iran’s Foreign Minister Javad Zarif in April. Evidence of military research, Sadjadpour said, “can be explained away as an elaborate Mossad-CIA conspiracy.”

Specifically, conceding guilt would mean admitting that Iran violated the terms of the Non-Proliferation Treaty, a United Nations pact governing the use of nuclear energy to which Iran is a signatory. Many of the U.N.’s tough economic sanctions on Iran are based on Tehran’s failure to cooperate with the IAEA’s investigation into its suspected military activity. A deal would eventually lift all nuclear-related sanctions on Iran — one of Tehran’s most basic demands — but the admission of guilt could hound Tehran for years and provide the U.S. with political leverage should disputes arise over Iran’s future compliance with a deal.

Khamenei issued his fatwa in October 2003 — a fateful time for Tehran. It was around then that Western intelligence agencies believe Iran halted its covert research into bomb-making techniques like explosives and reflectors. Some officials think the U.S. invasion of Iraq that March spooked Khamenei into halting the research and declaring nukes off-limits. It was also about a year after an Iranian opposition group first revealed the existence of Iran’s secret uranium-enrichment program, sounding alarms in Washington — and leading to talk of possible U.S. military action.

Critics of the nuclear talks say there can be no deal if the ayatollah doesn’t admit to treachery. “If the world allows you to lie about the past, this guarantees you will lie about the future,” said Yuval Steinitz, a senior Israeli minister who serves as his government’s point man for the Iran talks.

More practically, Steinitz added, knowing exactly what weapons research Iran conducted is crucial to identifying which locations and scientists to monitor most closely in the future.

That information could also shape the world’s understanding of a crucial question: Iran’s “breakout time,” or the amount of time it would take Tehran to dash to a bomb if it chose to do so, said Olli Heinonen, a former IAEA deputy director now with the Kennedy School of Government’s Belfer Center for Science and International Affairs at Harvard. “You need to know how far they got,” Heinonen said.

One way to achieve a face-saving deal could involve a resolution akin to an out-of-court settlement: Iran might answer the IAEA’s questions privately, over time, without admitting to the world that it did anything wrong.

Last week, Kerry hinted at why the U.S. might be satisfied with such an outcome. U.S. intelligence, he implied, paints a clear enough picture of Iran’s weapons research to make Iranian cooperation unnecessary. “We have absolute knowledge with respect to the certain military activities they were engaged in,” Kerry said.

But that statement was quickly challenged by critics of the talks. “I know of no American intelligence officer who would ever use that description to characterize what we know and do not know,” former CIA Director Michael Hayden wrote in The Washington Times.

While insisting on more clarity, the IAEA does not argue that full disclosure is necessary for a deal. That has “never been a precondition for reaching an agreement,” the agency’s director-general, Yukiya Amano, told Bloomberg News in April.

After a political framework was struck between Iran and the six world powers in April, a State Department fact sheet said only that “Iran will implement an agreed set of measures to address the IAEA’s concerns” regarding possible military dimensions of its program.

The vagueness of that language suggested to experts that Iran might be allowed to comply only partially with the IAEA and would not have to confess to any past military ambitions.

At issue now is just what those specific measures will be, including how much access IAEA inspectors will get to Iranian nuclear scientists and military bases. That question will be hammered out among negotiators in Vienna, where the talks are ongoing among experts and midlevel officials. Kerry is expected to join the talks late this month.

“The deal needs to strengthen the IAEA’s ability to get answers from Iran on past activities,” said Simond de Galbert, a former member of France’s Iran negotiating team who is now a visiting fellow at the Center for Strategic and International Studies. “The only way to do that is to condition sanctions relief to Iran taking significant steps with the IAEA to clarify [past nuclear research].”

A day after Kerry’s remarks, State Department spokesman John Kirby insisted that any nuclear deal would do just that.

“[S]anctions relief is only going to occur when those steps have been taken, including addressing possible military dimensions,” Kirby told reporters.

But addressing, experts noted, is not the same as admitting.