US Treasury Secretary Scott Bessent said on 26 September that a campaign to isolate Iran, which he called Operation Economic Outcast, is delivering results. "At my direction, teams were dispatched across the globe to engage with countries and demand action against the Iranian regime," he said. Turkey and Oman have halted incoming flights by the Iranian carrier Mahan Air and the UAE has stopped all flights by Iranian airlines; the UAE central bank blocked transactions involving Iran's Bank Melli and Turkey revoked the licence of Bank Mellat. The Treasury said it had engaged more than 50 countries on the initiative, while smaller Iranian carriers still fly international routes, notably to China.

Iran's Foreign Minister Abbas Araghchi said on 27 September that Tehran will not back down from its conditions for reopening the Strait of Hormuz. "Our conditions are clear, and any progress toward reopening the Strait of Hormuz depends on their fulfilment," he said. He added that Iran had received an initial response from President Trump but was waiting for the mediators' final positions before deciding its next steps.

Oman's Foreign Ministry said Foreign Minister Sayyid Badr Albusaidi met Iranian Foreign Minister Abbas Araghchi in New York on 26 September, during the 81st session of the UN General Assembly. It said they discussed safety and navigation in the Strait of Hormuz and stressed the importance of keeping passage free to support global trade and energy supplies.

Iran's armed forces spokesman Abolfazl Shekarchi warned on 27 September that Americans "dream of interfering in the Strait of Hormuz, and if they interfere in the Strait of Hormuz, they will be slapped", in remarks to the Tasnim news agency. He also said Iran, "as a world power", would never allow the United States to return to its previous position in the new world order.

Iran's Foreign Minister Abbas Araghchi said on 27 September that Tehran is still waiting for an official response from the United States to its proposal to reopen the Strait of Hormuz within seven days. Al Jazeera reported the remarks came shortly after President Trump publicly rejected the plan, with Araghchi saying he was awaiting word through mediators.

US Ambassador to the United Nations Mike Waltz told Fox News that a record 146 countries have condemned Iran's attacks on civilian shipping over the past 13 days. "A record 146 have stood with us in condemning those activities," he said, describing the attacks as acts of desperation.

Iran's Persian Gulf Strait Authority warned ship owners on 26 September that some charterers are forcing vessels onto unauthorised routes through the Strait of Hormuz. It said this risks "financial and life losses for the vessel, owner, master, and crew", and that charterers who do so will be placed on its Non-Compliance List, restricting future passage for all their ships.

President Trump told reporters on 26 September, "I reject their proposal," turning down Iran's seven-day roadmap to reopen the Strait of Hormuz. The plan asked the United States to lift its naval blockade, waive oil sanctions, release 12 billion dollars in frozen assets and observe a regional ceasefire.