Iran’s joint military command has warned that any oil tanker or commercial vessel transiting the Strait of Hormuz must use routes designated by the Islamic Republic or face what it described as an immediate and forceful armed response. The statement, carried by state-linked media on Thursday, coincided with a separate announcement by Iran’s ambassador to the United Nations that Tehran intends to begin imposing transit fees on ships passing through the strait after a 60-day grace period. The military headquarters, Khatam al-Anbiya, declared the waterway an “undisputed sovereign domain” of Iran and characterised the continued presence of US fighter jets and drones as a threat to regional security.

Viewed from Tehran, the warnings are a direct response to a US Central Command statement that, following a meeting with Middle Eastern partners in Bahrain, underscored a “shared commitment to the free flow of commerce” through the strait. Iranian officials interpreted that phrasing as an infringement on their sovereignty. At the UN Security Council, Ambassador Amir Saeid Iravani asserted that management of the strait is the exclusive responsibility of Iran and Oman, and that freedom of navigation would remain guaranteed without charge during the two-month period, after which fees would be introduced. He maintained that Iran remains committed to the 18 June memorandum of understanding with Washington, provided the United States fulfils its own commitments, and condemned a US strike on 27 June as a violation of that agreement.

International shipping unions and employers, however, are not treating the ceasefire as a return to normal conditions. The International Transport Workers’ Federation and the Joint Negotiating Group, which represents merchant shipowners, have extended the Strait of Hormuz’s designation as a warlike operations area at least until 9 July, with weekly reviews. The decision, the groups said, reflects the “continuing and significant risk to life” and the rapidly changing situation. Under the designation, seafarers are entitled to double pay and other benefits, raising operational costs for shipping lines. Italian defence officials estimate that hundreds of sophisticated mines laid during the conflict will take around two months to clear, a timeline that aligns with the grace period announced by Iran.

The strait has been a central fault line since the US-Israel war against Iran erupted on 28 February, a conflict that killed Supreme Leader Ayatollah Ali Khamenei in its opening hours. At least 14 seafarers have died and more than 40 vessels have been targeted. The 18 June memorandum of understanding called for a 60-day ceasefire extension, the lifting of a US naval blockade, and the full reopening of the strait. Technical negotiations toward a final accord, which would also address Iran’s nuclear programme, are continuing under joint Qatari-Pakistani mediation. The next concrete step is the weekly review of the war-zone designation, while the 60-day clock on free navigation and the potential introduction of transit fees has begun to run.