As the Trump administration calls for stricter monitoring of the Iranian nuclear agreement, officials in Iran insist they are complying with its terms and will not allow international inspectors into military sites.
Iran, which agreed in 2015 to grant inspectors broad access to nuclear-related facilities in exchange for the removal of severe economic sanctions, accuses President Trump of trying to sabotage what he has called the United States' "worst deal."
Trump has argued that Iran is violating the agreement struck under President Obama, although he has offered no evidence to support his claim and his administration has twice certified to Congress that Iran is in compliance.
But Trump administration officials looking for a way to increase pressure on Iran have begun to zero in on military facilities that they say could be used for nuclear-related activities barred under the agreement.
Inspectors with the International Atomic Energy Agency, the United Nations organization tasked with monitoring Iran's nuclear facilities, have not requested access to military sites since the agreement went into effect, according to experts monitoring the process.
The IAEA, in its most recent report in June, said Iran was meeting its obligations under the pact. Experts say inspectors rely on intelligence reports and other information to determine whether sites they have not visited are being used for potentially illicit purposes.
Last week, Trump's ambassador to the United Nations, Nikki Haley, took the administration's concerns to IAEA Director General Yukiya Amano in Vienna. Haley said the inspectors' reports "can only be as good as the access Iran grants to any facility the IAEA suspects of having a nuclear role," according to a U.S. summary of the meeting.
Iranian officials this week blasted Haley's comments, accusing the U.S. of fomenting a confrontation in order to withdraw from the deal.
"Americans will not be allowed to inspect the military bases," said Mohammad Bagher Nobakht, a member of Iran's nuclear implementation committee, according to state television.
Mohammad Nabi Habibi, secretary-general of the Islamic Coalition Party, which is close to Iranian Supreme Leader Ayatollah Ali Khamenei, said Iran had agreed to detailed inspections and not denied inspectors access to any facility.
"Why do the Americans want more?" Habibi said in an interview with the semi-official ILNA news agency. "I think the Americans are preparing to break up [the nuclear deal]."
For many Iranians — including those who support the nuclear deal — keeping inspectors out of military facilities is a point of national pride.
"It's our country, and any country's defense systems should be off-limits to international inspections," said Susan Saderi, a 44-year-old newspaper employee in Tehran. "I'd be unhappy if the government allowed inspections, even secretly."
Jaafari Mohammadi, a middle-aged motorcycle deliveryman, said access to the Parchin military complex outside Tehran was "a red line" for Iranians.
"We cannot compromise on our military sites," Mohammadi said. "It's our honor, or our wife — we cannot give access to others."
Iran has argued that inspections of military sites would violate national sovereignty, although the 2015 deal it signed with the United States and five other world powers allows inspectors to gain limited access to any site where illicit nuclear activity is suspected.
There is a growing debate among experts over whether inspectors should demand access to military sites, including those that in the past were suspected of being linked to nuclear-related activities.
Last week, the Institute for Science and International Security, a group of leading scientists that has argued for stricter monitoring of the Iran deal, released a report calling on the United States and other parties to the nuclear deal to require the IAEA to request access to the Parchin facility. The group believes Iran might have used the facility to conduct tests to see how certain materials react under high pressure, conditions similar to a nuclear explosion.
Iran denied inspectors access to Parchin for years, then finally granted access in 2015 after undertaking extensive construction work at the site, according to satellite imagery studied by the IAEA. Before the nuclear deal was approved, the IAEA agreed to accept limited access to Parchin in the future and to allow Iranian personnel — not the agency's own inspectors — to collect environmental samples at the facility for testing.
"The lack of ongoing access to Parchin calls into question the adequacy of the verification of the [nuclear deal] and the deal's long-term utility to deter Iran from obtaining nuclear weapons," the report said.
Mark Fitzpatrick, head of the nuclear policy program of the International Institute for Strategic Studies, said that nuclear verification programs rely greatly on cooperation from the host country and that IAEA inspectors would be reluctant to demand access to facilities without evidence of anomalies.
"Right now, if access [to military sites] were granted, it would look like Iran is buckling under pressure, and that's not something this government is going to want its people to think," Fitzpatrick said. "It's foolhardy of critics of the deal to demand IAEA access which will only result in a standoff — unless that's their real purpose."
Other analysts, however, believe Iran would be willing to compromise to avoid having the U.S. impose additional restrictions on its struggling economy. President Hassan Rouhani's government says the lifting of sanctions after the nuclear deal has boosted foreign oil sales and helped control inflation, although unemployment remains extremely high.
Nader Karimi Juni, an independent analyst, said Iranian officials want to avoid a confrontation with Trump and would probably be willing to grant limited access to Parchin and other sites to preserve the nuclear deal.
"Trump's rhetoric is not taken seriously even inside the U.S., and Iran has proven to be flexible and ready to negotiate when pressure flares up," Juni said.
"I think Iran may likely negotiate and give access to some military sites under some conditions, and the tensions will let up. But if the rhetoric escalates … then any military confrontation is possible because of a blunder by either side."
Mostaghim is a special correspondent.
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