• Secretary of State Marco Rubio says the U.S. has not yet received a response from Iran to its latest diplomatic overtures.
  • The administration maintains a dual-track approach of pressure and engagement, with deadlines looming for concrete concessions.
  • Failure to secure a deal could trigger additional sanctions or a shift in military posture, keeping energy markets on edge.

U.S. Secretary of State Marco Rubio stated on Thursday that Washington has not yet received a formal response from Tehran to its latest proposals, signaling that a breakthrough in nuclear talks remains elusive.

"We have not received a response yet," Rubio said during a press briefing, adding that the administration is "continuing to press for a clear signal" from Iran on its willingness to verifiably limit its nuclear program and ballistic missile activities. The remarks came amid a flurry of back-channel communications and diplomatic efforts, though no timeline for a reply was set.

The lack of a reply underscores the high-stakes standoff between the two nations, with the U.S. repeatedly linking progress to verifiable actions. "We need to see concrete steps, not just words," a senior State Department official said, speaking on condition of anonymity because they were not authorized to comment publicly. The administration has resisted proposals that would dilute international inspections or allow Tehran to delay compliance.

Meanwhile, the military option has not been taken off the table. U.S. Central Command has maintained a robust presence in the region, and policymakers have signaled a willingness to ramp up pressure if Iran fails to engage constructively. "We are prepared for all scenarios," a defense official said, declining to elaborate on specific contingency plans.

For energy markets, the stalemate adds a layer of uncertainty. Iran's role as a major oil producer and its control over the Strait of Hormuz have kept traders alert for any sign of escalation. Brent crude futures edged up 0.3% on the day, reflecting the geopolitical risk premium.

Efforts to restart negotiations have been complicated by Iran's recent nuclear advances and its support for regional proxies, according to people familiar with the matter. The administration has stressed that any deal must address both issues, rejecting partial agreements.

Without a breakthrough, analysts warn that the window for a diplomatic solution is narrowing. "If there's no response soon, we could see a new round of sanctions or even limited strikes," said a former U.S. diplomat familiar with the talks. "The clock is ticking."

The State Department declined to comment on potential next steps. Attempts to reach Iranian officials for comment were not successful.

Correction: An earlier version of this article misstated the timing of Rubio's remarks. They were made on Thursday, not Wednesday.