US Restrictions in the Strait of Hormuz and the Growing Risk for Shipping

Following the failed peace agreement talks with Iran, the United States has sent more than a dozen ships to restrict the vessels entering and leaving the Iranian ports.

Despite the agreement of a temporary ceasefire between the US and Iran, mediated through Pakistan, the United States has taken a further step that has placed the Strait of Hormuz under renewed pressure, raising concerns over the safety and predictability of shipping in the region. Following Tehran’s refusal to reopen the Strait, Donald Trump announced measures targeting vessels entering and leaving Iranian ports, supported by a significant US naval and air presence.

Irrespective of a vessel’s nationality, the US Navy aims to restrict ships linked to Iranian trade and supply chains. Naval forces have already been deployed across the region and, so far, have refused at least 13 vessels passage, according to recent Pentagon reports.

Up until this point, the closure of the Strait of Hormuz by Iran has caused significant legal controversy, as under the United Nations Convention on the Law of the Sea, the Strait is classified as an international strait in which all vessels are entitled to transit passage, regardless of nationality, and such passage shall not be impeded or suspended by any state.

The recent US restrictions, however, add a further layer of legal complexity to the matter. After the blockade, questions arise concerning whether the US is lawfully exercising belligerent rights to impose a targeted naval blockade under the Law of Armed Conflict at sea or whether its actions interfere with the established transit passage principles under international maritime law.

Although the temporary ceasefire, which is meant to last two weeks, initially raised hopes for the global shipping industry, those hopes have started to fade as matters escalate further.

The current measures illustrate how actions by major powers can not only affect global trade and energy markets, but also place pressure on the established legal framework governing maritime navigation.