The temporary ceasefire between the United States and Iran expired on Monday, and neither side moved to extend it. President Donald Trump told reporters that Iran was unlikely to accept the deal he wants, called for its surrender, and ruled out prolonging the arrangement. A senior Iranian official told Reuters that Tehran would shift to what was described as a fully offensive military posture, and promised an attack described as timely and precise.

What expired

The arrangement that lapsed was never a peace agreement. It was a memorandum of understanding with a defined end date — a pause with terms, not a settlement. That distinction matters for reading what happens next, and it is the reason its expiry does not automatically restart anything: nothing was resolved during it, and nothing was formally undone by its ending.

What did not happen during the pause is the substance of the problem. Talks on a permanent end to the war stalled. The Strait of Hormuz did not reopen. And the condition Iran has attached to reopening it — that Washington honour the June memorandum — has not moved, as we reported when Iran and Oman last discussed the strait.

The threat to Oman

Asked about reports that Iran and Oman were close to an agreement on managing the strait, Trump said he would bomb Oman if it obstructed efforts to reopen it. Oman is not a party to the war. It is the mediator, and it has been the back channel between Washington and Tehran for decades.

Threatening the mediator is unusual enough to be worth stating plainly rather than passing over. Analysts of Gulf diplomacy have long argued that Muscat’s usefulness rests on both sides believing it is not acting for the other. Whether a public threat damages that standing, strengthens Oman’s hand by demonstrating its independence, or simply passes without effect is not yet clear — and Oman has not responded publicly at the time of writing.

Resupply through the Caspian

NBC News, citing a European government document it obtained, reports that Russia has been shipping drone components, ammunition and explosives to Iran across the Caspian Sea, replenishing stockpiles depleted during the war.

The route is the interesting part. The Caspian is a closed sea bordered only by Russia, Iran, Azerbaijan, Kazakhstan and Turkmenistan. Nothing entering it passes a chokepoint controlled by anyone else, there is no Suez or Hormuz to watch, and there is no straightforward legal mechanism for a third country to interdict traffic on it. A supply line that cannot be intercepted at sea changes what pressure on Iran can realistically achieve.

The report rests on a single government document described to a news organisation. Neither Moscow nor Tehran has confirmed it, and documents of this kind reflect one government’s assessment rather than an established fact.

What “fully offensive” might mean

Language like this is designed to be read in several ways at once, and it is worth resisting the urge to translate it too confidently. It can describe a real change in military planning. It can be a negotiating signal aimed at the other side of a stalled talk. It can be aimed inward, at a domestic audience that wants to hear resolve.

What can be said is that the surrounding events are not rhetorical. Attacks on shipping in the strait have continued, including three strikes on UAE-linked tankers inside a week. Houthi forces in Yemen said on Monday they had attacked a Saudi military vessel and its escorts in the Red Sea. Drones struck the Kurdistan Regional Government in northern Iraq. The war is being fought in several places at once by parties who do not all answer to the same command.

The next confirmable event, rather than the next statement, is what will indicate whether the posture has actually changed.

Sources

• Just Security — Early Edition, 18 August 2026
• Democracy Now — headlines for 18 August 2026