By Arshad Mohammed and John Irish

WASHINGTON/PARIS (Reuters) – For nearly two years the United States has tried and failed to negotiate a revival of the 2015 Iran nuclear deal yet Washington and its European allies refuse to close the door to diplomacy.

Their reasons reflect the danger of alternative approaches, the unpredictable consequences of a military strike on Iran, and the belief that there is still time to alter Tehran’s course: even if it is inching toward making fissile material it is not there yet, nor has it mastered the technology to build a bomb, according to officials.

“I think that we do not have a better option than the JCPOA to ensure that Iran does not develop nuclear weapons,” Josep Borrell, the European Union’s foreign policy chief, said last week in Brussels after a meeting of EU officials, referring to the 2015 Joint Comprehensive Plan of Action under which Tehran reined in its nuclear program in return for relief from economic sanctions.

“We have to continue engaging as much as possible in trying to revive this deal.”

The uphill climb to revive the pact has grown steeper this year. Iran has brutally cracked down on popular protests, Iranian drones have allegedly made their way to aid Russia’s war in Ukraine and Tehran has accelerated its nuclear program, all of which raise the political price to giving Iran sanctions relief.

“Every day you see more and more pundits saying this is the worst time for reviving the deal and we should just be putting pressure on the wretched regime there,” said Robert Einhorn, a nonproliferation expert at the Brookings Institution think tank.

“There is a kind of resignation, even among the strong proponents of revival. Their hearts would be for paying the political price for a revival, but their heads tell them it would be really tough,” he added.

90% ENRICHMENT A RED LINE?

In 2018 former U.S. President Donald Trump reneged on the 2015 deal that, in a key provision, limited Tehran’s enrichment of uranium to a purity of 3.67%, far below the 90% considered bomb grade.

Trump reimposed U.S. sanctions on Iran, leading Tehran to resume previously banned nuclear work and reviving U.S., European and Israeli fears that Iran may seek an atomic bomb. Iran denies any such ambition.

Iran is now enriching uranium to 60%, including at Fordow, a site buried under a mountain, making it harder to destroy through bombardment.

Obtaining fissile material is considered the greatest obstacle to making a nuclear weapon but there are others, notably the technical challenge of designing a bomb.

A U.S. intelligence estimate disclosed in late 2007 assessed with high confidence that Iran was working to develop nuclear weapons until the fall of 2003, when it halted the weapons work.

Diplomats said they believed Iran had not begun enriching to 90%, which they said they viewed as a red line.

“If Iran were to clearly restart its military program and enrich at 90% then the entire debate changes in the United States, Europe and Israel,” said a Western diplomat, saying the diplomatic path would remain open unless that happened.U.S. politicians have grown more hostile to cutting a deal because of Iran’s ruthless crackdown on protests that began after a 22-year-old Kurdish Iranian woman, Mahsa Amini, died in September in the custody of Iran’s morality police.

U.S. President Joe Biden’s administration has intensified sanctions against Iran in recent months, targeting Chinese entities facilitating sales of Iranian crude and penalizing Iranian officials for human rights abuses.

Still, even though negotiations are stalled Enrique Mora, the European diplomat who coordinates the nuclear talks, “keeps talking to all sides,” said a senior Biden administration official who spoke on condition of anonymity.

“We will continue with the pressure while keeping the door open for a return to diplomacy,” U.S. special envoy for Iran Robert Malley told reporters in Paris last month, adding that if Iran crossed “a new threshold in its nuclear program, obviously the response will be different.” He did not elaborate.

Iran has linked a revival of the deal to the closure of investigations by the International Atomic Energy Agency (IAEA) into uranium traces at three sites. The United States and its allies have not agreed to that condition.

DIPLOMACY MAY LIVE EVEN IF JCPOA DIES

Several Western diplomats said they did not believe there was any imminent consideration of military action against Iran and suggested a strike could simply reinforce any Iranian desire to obtain nuclear weapons and risk Iranian retaliation.

“I do not think … anybody is envisaging a military option in the near-term,” said the Western diplomat. “The solution isn’t going to be military and I don’t hear a lot of people calling for one.” 

    A third diplomat said he thought it practically impossible for Israel to bomb Iran without Western support.

Even if the 2015 nuclear deal cannot be resurrected, the senior Biden administration official said other diplomatic solutions might be possible.

“Whether, when and how the JCPOA can be revived is a difficult question,” he said. “But even if, at some point, the JCPOA were to die, that would not mean that diplomacy would be buried at the same time.”

(This story has been refiled to turn two sentences into one for greater clarity in paragraph 3)

(Reporting by Arshad Mohammed in Washington and John Irish in Paris; Editing by Don Durfee and Daniel Wallis)

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