US-Iran Ceasefire Collapses: June 2026 Timeline of Strikes, Strait of Hormuz Claims, and Stalled Talks

Iran Immediately Claimed Exclusive Control

From the moment the MOU was signed, Iran asserted an interpretation that gave it authority to regulate transit through the Strait of Hormuz. The Institute for the Study of War (ISW) reported that Iran claimed the final MOU text satisfied its key war aims, including over the strait, and that Tehran interprets the text as giving it the power to control passage .

By June 23, Iran had begun taking concrete steps to institutionalize that control. ISW documented that Iran was moving to establish a joint mechanism with Oman that would allow it to exercise long-term authority over the strait and restrict passage at its discretion .

The Guardian noted that the MOU was "too broadly worded," allowing each side to claim conflicting interpretations . The language in Article 5 of the MOU, which tasked Iran with making "best efforts" to ensure safe passage and left the terms "arrangements" and "best efforts" ambiguous, became a particular point of contention .

The Ceasefire Collapses: Drone Strikes on Tankers

June 26: Trump Accuses Iran of Violating the Truce

On Thursday, June 25 or early Friday June 26, President Trump posted on Truth Social that Iran had violated the ceasefire after "at least four" one-way attack drones targeted cargo ships transiting the Strait of Hormuz. One drone "solidly hit the upper deck of a large and very expensive" cargo ship, though the vessel was "able to proceed" . Trump called the attack a "foolish violation" .

Hours later, US Central Command (CENTCOM) said it had conducted strikes against Iranian missile and drone storage locations and coastal radar sites in response .

June 27: Tanker MT Kiku Struck by Iranian Drone

On Saturday, June 27, a Panama-flagged tanker, the MT Kiku, was struck by an Iranian drone in the Strait of Hormuz. Britain's UKMTO maritime security agency confirmed the bridge was damaged but reported all crew were safe .

The same day, the US launched a second night of strikes on Iran, hitting military surveillance infrastructure, communication systems, air defense sites, drone storage facilities, and minelayer capabilities along the strait—targeting locations around Sirik, Bandar-e Lengeh, and Qeshm Island . CENTCOM described the strikes as "self-defense" and said they were "in direct response to continued Iranian aggression against commercial shipping" .

The escalation was described as the worst since the MOU was signed two weeks earlier .

Iran Strikes Kuwait and Bahrain

June 28: Missile and Drone Attacks on US Allies

On Sunday, June 28, Iran launched drone and missile attacks targeting Bahrain and Kuwait in direct retaliation for the latest US airstrikes, according to the Associated Press .

The Islamic Revolutionary Guard Corps (IRGC) claimed responsibility, saying it struck the US Fifth Fleet headquarters in Bahrain and the Ali Al Salem Air Base in Kuwait . Air raid sirens sounded in Bahrain, and Kuwait confirmed its air defenses were responding to "hostile missile and drone threats" . Kuwait said air defenses intercepted Iranian drones and two missiles; no injuries or damage were reported .

This was not the first such attack. Iran had also struck Bahrain, Kuwait, and Jordan earlier in June before the MOU was signed . But the June 28 attacks represented the sharpest escalation since the deal was signed .

The Strategic Stakes: Why the Strait of Hormuz Matters

The Strait of Hormuz is the world's most critical oil chokepoint. Approximately 20% of global oil consumption—about 17–20 million barrels per day—passes through it in peacetime . When the MOU was signed and the US lifted its naval blockade on June 18, global energy markets reacted sharply: Brent crude dropped 8.5% to about $80.59 per barrel .

By June 19, the energy tracking firm Global Energy Flow rated the strait's status as "ELEVATED (recovery-fragile)" . After the renewed hostilities, the waterway's status was once again uncertain.

Negotiations: Stalled and Threatened with Termination

As of June 28, the negotiation process had stalled. Iran explicitly threatened a "complete halt" in negotiations if Washington continued its strikes .

No new rounds of talks were scheduled. The Guardian reported on June 28 that the ceasefire was "close to collapse" and that the MOU had failed to resolve core disputes over Hormuz governance and the terms of the Lebanon ceasefire . Iran's Foreign Minister Abbas Araghchi stated that Iran would exercise sole management and oversight of the strait for the next 30 days before allowing full traffic to resume .

Bottom Line

The US-Iran interim peace deal signed on June 17, 2026, unravelled in just 11 days. By June 28, both sides had traded escalating strikes over the Strait of Hormuz, Iran had attacked Gulf neighbors, and negotiations were threatened with a complete halt. The core unresolved issue—who controls the Strait of Hormuz—remains the central flashpoint, with Iran claiming exclusive authority under an ambiguously worded MOU and the US accusing Iran of violating the ceasefire's terms.