The Collapse of the US-Iran Interim Peace Deal: From the Islamabad Memorandum to the Seventh Night of Strikes

The US-Iran interim peace deal, signed with high hopes in June 2026, collapsed in less than a month. The unraveling was rapid and catastrophic, triggered by clashing interpretations of a single clause in the agreement. This article provides a source-backed account of the collapse, Iran's specific responses—including the condemnation of the attack on the strategic Chabahar Port—and the state of open conflict as it entered a seventh consecutive night of strikes.

What Led to the Collapse of the US–Iran Interim Peace Deal

The interim ceasefire, known as the Islamabad Memorandum, was signed on June 17, 2026, under Pakistani mediation . It was intended to provide a 60-day window for negotiations on a permanent peace agreement . Within three weeks, it lay in ruins. The collapse was driven by three interconnected factors:

1. The Strait of Hormuz ‘Traffic Management’ Dispute

The deal contained a clause that Iran interpreted as granting it the right to manage shipping traffic through the Strait of Hormuz. The United States viewed any Iranian actions under this clause as attacks on commercial vessels . On July 7, three tankers were hit in the strait, which the US blamed on Iran . This clash over interpretation was the immediate trigger for the deal's failure. As the AP noted, the clause seemed to be "the undoing of the deal" .

2. US Retaliatory Strikes and Reimposed Oil Sanctions

Hours after the tanker attacks, the US military launched a new wave of strikes against Iran. The US also revoked Iran's license to sell oil and reimposed oil sanctions . The initial wave of strikes hit over 80 Iranian locations .

3. Both Sides Declare the Accord Dead

On July 8, President Donald Trump stated that the memorandum was "over" and that he did not want to engage with Tehran . Iran responded in kind. On July 15, Tehran declared that the repeated US attacks had "voided" the memorandum, with Iranian Parliament Speaker Mohammad Bagher Ghalibaf stating that Iran was "in an essential and existential war with America" and had no reason to continue adhering to the agreement's terms .

Iran’s Response to the US Strike on Chabahar Port

US strikes hit Iran's Shahid Kalantari Port in Chabahar—a strategically important, India-backed port—on the second night of the renewed US campaign (July 9) . Iran's response was multi-pronged:

Condemnation from the Iranian Embassy in India

On July 18, the Iranian Embassy in India issued a strong condemnation, labeling the US strike on the Chabahar Port a "war crime." The statement specifically cited the destruction of a surveillance tower at the port, calling the action a "flagrant violation of international law and the Charter of the United Nations" .

Response from the Supreme Leader’s Office

It is crucial to note the change in leadership. A February 2026 US-Israeli strike had killed Ayatollah Ali Khamenei, and his successor Mojtaba Khamenei had assumed the role . By the time of the Chabahar strike in July, a military adviser to the new Supreme Leader, Major General Mohsen Rezaei, issued a stark warning. He stated that Tehran would resume "full-scale offensive operations" if US strikes continued for another two or three days .

The Chabahar Project’s Status

Despite the strike and ongoing war, Iran's Ambassador to India publicly stated that the Chabahar project remained on track . India later confirmed that the Shahid Beheshti terminal at the port had suffered no damage from the strikes .

The Conflict on the Seventh Consecutive Night

As of July 17–18, 2026, the US and Iran were engaged in an intense, open-ended exchange of fire for the seventh consecutive night .

• US Actions: US Central Command (CENTCOM) launched strikes beginning at 19:00 GMT (3:00 PM ET), targeting "surveillance sites, military logistics infrastructure, underground weapons storage, and maritime capabilities" . The US also enforced a strict naval blockade in the Strait of Hormuz . By this point, Iranian state media reported at least 38 deaths and over 400 injuries from the renewed strikes .
• Iranian Retaliation: Iran struck multiple US military sites in Kuwait, Jordan, and Iraq . Iran's Revolutionary Guard had earlier claimed to have targeted 85 US sites in response to the initial strikes .
• No Ceasefire in Effect: With the interim peace deal void and no new truce in place, both sides described the conflict as open-ended and existential .