Iran closed the Strait of Hormuz on Wednesday, after Washington said it rejected key facets of Tehran's 10-point peace plan, and Israel ramped up its bombing of Lebanon, risking the US-Iran truce.
Iran has demanded as part of its 10-point plan that the Strait of Hormuz remain under its control, and has also insisted on its right to enriched uranium.
US President Donald Trump initially signalled a positive outlook on the prospect of reaching a deal with Iran, going so far as to suggest that Tehran and Washington could jointly collect toll fees from the Strait of Hormuz.
"We’re thinking of doing it as a joint venture,” Trump told ABC News 's Johnathan Karl. "It's a way of securing it - also securing it from lots of other people. It’s a beautiful thing."
Hours later, however, the president hardened his tone, demanding that Iran reopen the waterway and claiming that the ceasefire proposal received by Washington was not the same as the one being circulated in the media. Israel on Wednesday carried out more than a hundred strikes on Lebanon - including on the capital Beirut - killing at least 203 people.
In response, Iran announced it had closed the Strait of Hormuz, accusing the US and Israel of violating the two-week ceasefire deal.
Later, Russian state media, quoting an IRGC official, said Iran would not allow more than 15 ships a day to pass through the strait.
Ship-tracking data from trade and analytics platform Kpler showed only four vessels with their Automatic Identification System trackers switched on passing through the Strait of Hormuz on Wednesday on the first day of the ceasefire.
However, this total does not include so-called “dark fleet” vessels - those with their AIS trackers turned off.
Many of those “dark fleet” ships carry sanctioned Iranian crude oil out to the open market.
There have been no further reports of oil tankers passing through the strait.
On Thursday, semi-official news agencies in Iran published a chart suggesting the country’s Iranian Revolutionary Guard Corps (IRGC) had put sea mines into the Strait of Hormuz during the war.
The chart, released by the ISNA news agency and Tasnim , which is believed to be close to the IRGC, shows a large circle marked “danger zone” in Persian over the Traffic Separation Scheme. This is the route ships take through the Strait of Hormuz, the narrow mouth of the Gulf through which 20 percent of all oil and natural gas traded once passed.
The chart suggested ships travel further north through waters closer to Iran’s mainland near Larak Island, a route that some ships were observed taking during the war. It was dated from 28 February until Thursday, 9 April, and it was unclear whether the IRGC had cleared any of the mines in the waters since then.
Meanwhile, European leaders have called for a complete reopening of the Strait of Hormuz, pushing back against Iran's continued control and fee imposition.
Italian Prime Minister Giorgia Meloni said on Thursday that restoring freedom of navigation in the Strait of Hormuz is a vital interest for her country and the whole of the European Union.
"We have come within a step of the point of no return, but we now face a fragile prospect of peace that must be pursued with determination,” Meloni told parliament, adding that Italy condemns any violation of the ceasefire and is calling for a permanent halt to hostilities.
UK Foreign Minister Yvette Cooper also called for the strait to be reopened, saying it should be toll-free.
Earlier in the conflict, US President Donald Trump suggested that he would abandon trying to wrest control of the strait, suggesting it was the responsibility of European allies, who import energy via the waterway, to take charge.
As the fragile ceasefire holds, negotiations are slated to go ahead in Pakistan on Monday, with Washington sending top Trump aides Jared Kushner and Steve Witkoff to lead its team. The future of the Strait of Hormuz will weigh heavily on the agenda, with Iran viewing its control over the passageway as a key deterrent for future attacks.