• U.S. negotiators estimate an 80%-85% probability of signing a nuclear deal with Iran, citing progress on key sticking points.
  • The potential agreement could ease sanctions, impacting global oil markets and regional geopolitics.
  • Remaining hurdles include enrichment limits, sanctions relief scope, and verification mechanisms.

Optimism Builds in Vienna Talks

The Biden administration has signaled growing confidence that a nuclear agreement with Iran is within reach, with U.S. officials now placing the odds of a signed deal at 80% to 85%, according to people familiar with the matter. The assessment, shared with allies this week, reflects significant narrowing of differences in ongoing negotiations in Vienna.

“We’re closer than we’ve ever been,” a U.S. diplomat involved in the talks said, speaking on condition of anonymity. “But the final stretch is always the hardest.”

Iranian negotiators have similarly expressed cautious optimism, though they continue to demand guarantees that sanctions relief will be durable and not subject to future U.S. political shifts. The potential breakthrough follows months of shuttle diplomacy mediated by European officials.

Key Hurdles Remain

Despite the upbeat probability estimate, several critical issues remain unresolved. The two sides are still grappling over the extent of Iran’s uranium enrichment program, particularly the level of enrichment and stockpile limits. The U.S. is pushing for stringent IAEA inspection access to ensure compliance, while Iran seeks a swift and broad lifting of sanctions.

“Without a credible verification regime, any deal is just a piece of paper,” a senior administration official said. Iranian negotiators, however, have pushed back against what they see as intrusive demands.

Market Implications

News of the high probability has already rippled through oil markets, with Brent crude dipping 2% on Thursday as traders priced in the potential return of Iranian supply. Analysts estimate Iran could add roughly 1 million barrels per day within months of sanctions relief.

“Markets are starting to bake in a deal,” said a energy strategist at a major investment bank. “But the real impact depends on the final terms and timing.”

Regional Gulf states, meanwhile, are watching closely, worried that a resurgent Iran could shift the balance of power. Israeli officials have voiced strong opposition to any agreement they deem insufficient.

What’s Next

The coming days are expected to bring intensified diplomatic efforts, with EU foreign policy chief Josep Borrell shuttling between delegations. A final text could emerge within weeks, though both sides caution that the talks could still collapse over last-minute disagreements.

The administration has stressed that no deal is done until it’s signed. “We’re not popping champagne yet,” the U.S. diplomat said.

Correction: An earlier version of this article misstated the probability range. It is 80%-85%, not 85%-90%.