How the second phase of the Iran-U.S. war started and why it is raging | Explained
A ceasefire framework between the United States and Iran, negotiated in mid-June and formally signed on June 17 (the "Islamabad Memorandum"), included a Memorandum of Understanding (MoU) on the Strait of Hormuz that allowed commercial vessels to transit "with no charge, for 60 days only," with Iran and Oman to jointly work out longer-term administration of the strait's maritime services.
The MoU also set a 60-day window for the two sides to negotiate a final settlement covering outstanding issues, including Iran's uranium enrichment program.
Renewed attacks on commercial shipping in the Strait of Hormuz through late June and July led to a breakdown of the truce, with both sides resuming military strikes.
The core dispute concerns interpretation of the MoU: Iran maintains it retains authority over passage arrangements in the strait, while the United States holds that the pact commits to a fully open waterway once the 60-day window lapses.
The resumption of hostilities has disrupted oil tanker traffic through the strait, a route that normally carries roughly a fifth of the world's traded oil.
Strait of Hormuz — Geography and Strategic Significance
The Strait of Hormuz is a narrow sea passage between the Persian Gulf and the Gulf of Oman, bordered by Iran to the north and Oman's Musandam Peninsula (with a UAE enclave) to the south. It is the world's most important oil "chokepoint" — a narrow channel through which a disproportionate share of global energy trade must pass, making it strategically vital and vulnerable to disruption.
Key Details
- The strait is about 167 km long, narrowing to roughly 33-39 km at its narrowest point, with shipping lanes only about 3 km wide in each direction.
- It carries close to a fifth to a quarter of the world's total oil trade and is the primary export route for Saudi Arabia, Iraq, UAE, Kuwait, Qatar, Bahrain and Iran; it also carries a large share of global LNG exports (Qatar and UAE cargoes transit almost entirely through it).
- The strait falls under the maritime jurisdiction framework of UNCLOS (UN Convention on the Law of the Sea, 1982), specifically the "transit passage" regime for straits used for international navigation — though Iran has not ratified UNCLOS and disputes aspects of its application.
- Historically, threats to close the strait have been made by Iran during periods of tension (e.g., 2011-12, 2019), but a sustained closure had not occurred prior to the 2026 conflict.
The dispute over whether Iran or a joint Iran-Oman arrangement controls "administration and maritime services" in the strait is the direct trigger for the collapse of the truce, since both countries interpret the MoU's transit provisions differently.
Memorandum of Understanding vs. Treaty — International Instrument Types
An MoU is typically a non-binding or politically (rather than legally) binding instrument recording an understanding between parties, distinct from a treaty, which creates binding legal obligations under international law and, for India, would require ratification per constitutional practice. Naming a ceasefire arrangement after its signing location (as with the "Islamabad Memorandum" here) follows a pattern seen in agreements like the Simla Agreement (1972) or the Abraham Accords (2020).
Key Details
- Under the Vienna Convention on the Law of Treaties (1969), a document's binding character depends on the parties' intent, not merely its title — an "MoU" can sometimes be legally binding if the language indicates intent to create obligations.
- India's own treaty-making practice is governed by Article 253 of the Constitution (Parliament's power to legislate for implementing international agreements) and Entry 14 of the Union List (treaties and agreements with foreign countries).
- Time-bound, renegotiable ceasefire MoUs (like the 60-day window here) are a recognised category of conflict-management instruments, distinct from final peace treaties.
The ambiguity of an MoU's binding force is precisely what allowed both the U.S. and Iran to advance conflicting interpretations of the Strait of Hormuz provisions, contributing to the ceasefire's collapse.
India's Energy Security and West Asia Policy
India has repeatedly stated its position on West Asia conflicts, calling on all parties to exercise restraint, de-escalate, protect civilians, and ensure the uninterrupted flow of energy supplies and commerce, while urging a return to dialogue and diplomacy. This reflects India's broader "multi-alignment" approach — engaging major and regional powers without formal alliance commitments — and its acute dependence on Gulf energy supplies.
Key Details
- India imports over 80% of its crude oil requirement; Gulf countries (Iraq, Saudi Arabia, UAE, Kuwait) together have historically supplied roughly 60% of India's crude imports, though this share has been diversifying downward from about 72% (2017-18).
- The Ministry of Finance's Monthly Economic Review has flagged the duration of Strait of Hormuz disruption as the single most consequential variable for India's external sector and inflation outlook.
- India has sought to mitigate exposure by diversifying suppliers (including Russia and non-Gulf sources) and by re-routing a larger share of crude imports outside the strait.
- India also has direct strategic stakes in the region through the Chabahar Port project in Iran (part of the International North-South Transport Corridor, INSTC) and a large expatriate workforce in Gulf states.
A prolonged closure or contested control of the Strait of Hormuz directly threatens India's energy import costs and the safety of its shipping and diaspora interests, explaining why India's official statements consistently prioritise "uninterrupted energy supplies" alongside calls for de-escalation.
- Islamabad Memorandum: preliminary agreement reached mid-June 2026, formally signed June 17, 2026, by the U.S. and Iranian presidents.
- MoU set a 60-day window for a final settlement and 60 days of no-charge commercial passage through the Strait of Hormuz.
- Strait of Hormuz carries an estimated 20-25% of global seaborne oil trade and roughly 19% of global LNG trade.
- Strait width: approximately 167 km long; narrows to about 33-39 km at its narrowest point.
- India's crude oil import dependence: over 80% of domestic consumption; Gulf share historically around 60-63% of India's crude imports.